No. 557.

LONDON, SATURDAY, MAY 3, 1834.

UNIVERSITY OF LONDON.

LECTURES

ON

COMPARATIVE ANATOMY

AND

ANIMAL PHYSIOLOGY,DELIVERED BY

ROBERT E. GRANT, M.D., F. R. S. E.,&c., &c.;

Fellow of the Roy. Coll. of Physicians of Edin.;and Professor of Comparative Anatomy and Ani-mal Physiology in the University of London.

LECTURE XXVIII.ON THE OSTEOLOGY OF QUADRUMANA

AND BIMANA.

ALL transitions in organic forms are

effected by imperceptihle gradations, andaccording to determinate and uniformlaws. This is not more obvious in the

separate systems of internal organizationthan in the outward shape of the entireaggregates. So that there can be no or-

gans developed in the semi-erect climbingyuadruraanous animals, or in the erect bi-mana, which have not passed through theirphases of development in the inferior tribes.Without galagos and loris and lemurs, theorganization of the higher quadrumanawould be as anomalous as that of manwould appear, without gibbons and orangs,and chimpanzes and negros. The batsand the galeopitheci lead us to the lemursand the monkey tribes, for the cheirop-tera present numerous affinities to the ’’

quadrumana, both in their solid and theirsoft parts, as in the possession and theproximity and the forms of the three kindsof teeth, the complete and constant de-velopment of the clavicles, the form of thescapula, the great development of thehand, and the freedom of the thumb, theprehensile character of the foot, the formof the stomach, the alimentary canal, and

the coecuin-coli, the scrotal testes, the

pendent penis, and the pectoral mammse.The quadrummw have received this name

from the opposable nature of the greattoe on the hind feet, as well as that of thethumb on the anterior extremities, andthey are sometimes designated by theGreek appellation tetracheira, to corre-

spond with the name of the last ordercheiroptera, the most obvious and constantcharacter of the present order being thepossession of four hands. They comenearest to man in the form and propor-tions of their skeleton, and of their sepa-rate bones-in the general disposition oftheir muscular system, and its adaptationfor a semi-erect position of the body-intheir great cerebral development, the per-fection and the equable development oftheir orsans of the senses, their intel-lectual capacity and complicated instincts-in the character of their digestive, theircirculating, their respiratory, and their

glandular apparatus, and in all that re-lates to the production and rearing oftheir young. These most elevated of allthe inferior animals are organized to se-lect, to obtain, and to digest, the succulentripe fruits of trees, and to inhabit the richand shady forests of tropical climates.

They leave to the squirrels and the slothsthe buds and the leaves, to the ponderouselephants and rhinoceroses the branchesand the stems, and to the beavers andother rodentia the dry bark of the trees.Their delicate organization is adapted onlyfor the richest products of the vegetablekingdom, and from the soft and nutritiousquality of their food, the broad enamelledcrowns of their molar teeth are studdedwith rounded tubercles, their stomach issimple, their intestine moderate, and theircaecum-coli comparatively small. With ahigh cerebral and muscular development,corresponding with their elevated rank inthe scale, and the elevated position of theirfood on the trees, they are the most agileand sportive of all the mammalia, and tosuit their climbing habits they are pro-vided with prehensile organs at everypoint; their teeth, their tail, their feet,their hands, assist in their gambling move.

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ments, and in their boundings from branchto branch, and from tree to tree, or in I

their struggles with their numerous as-sailants lurking among the branches. IFrom this inclined position of the trunkin climbing, we observe all parts of theirskeleton and of their internal organsadapted for the semi-erect posture of the Ibody; and from the weight of their trunk Ibeing thus relieved from that of the extre-mities, by their numerous prehensile or-gans, and the inclined or suspended positionof their body, the whole bones of the ske-leton partake of those slender, lengthened,and light proportions, which are best suit-edfor their nimble movements. You see

nothing of those massive pillars whichsupport the heavy horizontal trunks ofthe larger quadrupeds, in the light andelastic limbs of the quadrumana. -

Though the richest fruits are the natu-ral and favourite food of this order, thegreater number of the inferior quadru-mana partake willingly of the mixed kindof food of insectivorous animals, feedingon insects, which many of them seize whenupon the wing, on the eggs of birds, oreven on fishes which they take from thewater,’ as well as on seeds, and grains,and fruits. This kind of life, and habi-tual position of the trunk, require themto have the head more balanced and sup-ported upon the two condyloid processesof the occipital bone than in those hori-zontal forms of quadrupeds where thehead is suspended vertically at the end ofthe vertebral column, by a strong andelastic ligamentum nuchae, passieg back-wards to the dorsal vertebrae. We there-fore find that in these quadrumanous ani-mals the occipital foramen, by the en- ’largement of the superior laminae of thecranial vertebrae, has advanced under thebase of the cranium to a considerable ex-tent forwards towards the centre, so thatthey require much less of that ligamen-tous attachment and suspension of the i,head, which is so common and powerful iin the larger quadrupeds, and is calculatedto impede its motions, while it gives se-curity for the support of its great weight.The animals that we are speaking of

are capable of the most active and livelymovements, which is an endowment ne- I

cessary for the simple act of climbing alofton trees for their food ; but when we ob-serve the innumerable enemies which theyhave to encounter upon the trees, the

cunning and stratagem which they mustoften have recourse to for self-defence,and for obtaining their food when it con-sists of living insects, we see that theyrequire to have a disposition of all theirbones and muscles calculated to give ve-locity and extent to the movements of the I

joints, rather than security and strength.I We are advancing to that form and atti-tude of the whole frame which charac-

terizes our species,-the cntireiy erect

position of the trunk, and to that form andstructure of all the internal organs whichare the most elevated in development, orthe most perfect to which organization hasyet reached upon the surface of this planet;and the intermediate gradations to the

human form are, therefore, here in thehighest degree interesting, as they affecteach particular part, both of the solid

frame-work and of the softer internal

organs. In ascending from the iiisceti-vorous quadrupeds and bats, through thelemurs and baboons to the gibbons andthe orangs, we arrive gradually at thaterect position, those graceful proportions,and that commanding attitude of the wholeframe, which appear so peculiar to ourspecies, from our being less familiar with

the connecting links,-the highest of thequadrumana, and the lowest ofthebhnana,1 concealed in the inaccessible wilds of tro-

pical forests.I In that soft-furred, warm-clad, noc-

turnal species, the fox-muzzled lemurs of! Madagascar, as in this of the Mccoco orlemur catta (Fig. 114), we still find the

lengthened form of the skull and face, the

numerous molar teeth, and the adaptation,in the whole skeleton, for the horizontalposture of the trunk, which is common tomost of the inferior orders of mammalia.

The occipital foramen is still situated atthe posterior margin of the cranium, anddirected obliquely downwards and for-wards. The mastoid cells are as large asthose of a carnivorous quadruped, and al-though the orbit is surrounded by anosseous margin, it is continuous behindwith the temporal fossa. The human su-tures are here permanent, and corre-

spond with the great development of thecranial cavity, and of the hemispheres ofthe brain. The sagittal suture continuesonwards through the frontal bone, and theanterior frontal;, are as distinct as iit thecrocodiles, between the frontal, nasal,maxillary, and lachrymal bones. The

temporal muscles are feeble, the skull isarched laterally, the temporal fossa small,

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the zygomatic arch feeble and almosthorizontal, and the glenoid surface is flat, 1:for the transverse flat condyle of thelower jaw. The lachrymal bones extend;’ emuch from the orbits over the face, and ;are perforated on their facial portion. The vnasal bones, unlike those of the higherquadrumana, are long, straight longitu- Idiuaily, separate, broad, expanded above,and arched laterally throughout theircourse. The upper and lower maxillarybones have a lengthened form to afford

space for numerous teeth, and the condyle ’of the lower jaw is nearly as low as the ialveoli of the teeth, from the shortness ofthe ramus. The angle of the lower jaw i ,

passes acutely backwards, and the coro- noid process mounts upwards to a greatdistance through the zygomatic arch. The’- v

inferior incisor teeth, four in number, asin the simiæ and man, project straightfrom the jaw like the inferior incisors of akanguroo, as they do also in the stenopsand galago and lichanolus. The propoll-tions of the face and of the whole head Ibecome shortened, as we ascend from the

imakis, and loris, and tarsius, and galago, iand lichanotus, to the ouistitis and theother simiae of the old and new continent. ILooking at the sutures of the skull in

the simiae, we find that they have the samegeneral disposition as in the human skull.!The frontal bone has its two portions earlyunited in these quadrumanous animals,and the slightly arched frontal bone is se- lparated from the expanded and smoothparietals, by a high coronal suture. The

parietals, which we have so commonly seenunited and anchvlosed in the carnivorousquadrupeds, in the cheiroptera, and in imany of the inferior grades and classes of Ivertebrata, are here permanently detached,as in man. The lambdoidal, the sagittal, ithe squamous, and the coronal sutures ad-vance forwards on the cranium, more andmore, as the cerebral centres developwithin, and enlarge the cranial cavity. Thenumber and the permanence of the sutures !in the quadrumana and in man appear to:be intimately connected with, or depend -)ent on, the high degree of development ofthe great nervous centres. A rapid processof ossification in the cranium is necessaryto keep these numerous bones in conjunc- ’tion at their margins during the rapid delve-lopment and growth of the enclosed brain;and this rapid extension and expansion of ithe contained parts prevent the bonesfrom anchylosing. They require more:numerous points for receiving increased,!which points are given to them by havingthese numerous sutures traversing allparts of the head. We perceive that theface in the simiae is greatly diminished, inits proportion to the cranial cavity, when

compared with the long - muzzled le-murs and inferior animals we have beenhitherto considering. Those organs ofthe senses, lodged in the face, which weperceived comparatively so large in theinferior animals, are obviously beginninghere to occupy a much smaller propor-tional space, and the face which containsthose organs is thus becoming proportion-ally small as we ascend in the scale, com-pared with the cavity of the cranium forthe great cerebral centres, the seat of allthe intellectual operations.

Give large ears to an ass, to beat withauditory impressions upon its dull brain,or to hear the braying of its mate; givelarge eyes to the almost brainless fish, tosteer its course in the dark abyss; givelarge nostrils to a dog to hunt its prey; buthere, in the sagacious monkeys, we havegot a watchful sentinel within the cra-

nium, which requires but a hint to giveit a lively perception. A hint is enoughto the wise. It is the proportional develop-ment of the great centres of nervous

energy, which impresses an elevated hu-man-like form on their head, and alsocauses the parallelism of their orbits.As the muzzle thus shortens, the facial

angle enlarges, by the elevation and pro-jection of the frontal bone, and by this

shortening of the jaws less space is afford-ed for numerous molar teeth. The orbitsapproximate, assume a parallel directionforwards, separated only by a narrow eth-moid, and they become separated by anosseous partition, formed by the frontaland malar bones, from the temporal fossa.The temporalfossa becomes reduced in size,the zygomatic arch short and straight, thecondyloid articulation flat and free, thelachrymal bone confined to the orbit, andthe nasal bones flat, narrow, short, andoften anchylosed together. The intermax-illary bones continue as permanently se-parate bones, up to the orangs, and the in-cisors above and below are the same in. number as in man, but those teeth are

) inclined outwards. The canine teeth, as

instruments of defence and of prehension,continue largely developed, and the sharptubercles of the molar teeth of the insec-- tivorous and nocturnal makis, become.more flat and rounded in the higher qua-drumana, corresponding with the softer

quality of their succulent and juicy food.The simiæ of the old continent have the-same number of teeth, or the same dental. formula, as man; but those of Americahave an additional molar tooth on each

I side of each jaw, excepting the two small ouistitis, the iacchus, and the midas, whichhave the same number as in the human

jaws.

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In the powerful muscular dog-facedbaboons, the cynocephali (Fig. 115) of

Africa and Asia, the muzzle is length-ened as in the lemurs, the facial angle isnearly as low as thirty degrees, the tusksare large as in a wolf, the skeleton is adapt-ed for the horizontal posture, and the ani-.mals are strong and fierce; yet even thesepresent in the minuter details of their ske-leton a very close approximation to thehigher quadrumana. The four incisorsabove and below are large, and nearly per-pendicular ; the dental formula is the sameas the human, the molar teeth have broadcrowns, with a double row of compara-tively rounded tubercles, their nasal bonesare narrow, depressed, and anchylosed to-gether, their orbits are parallel, approxi-mated, and completely separated by anosseous septum from the temporal fossae,the lachrymal bone and groove are con-fined to the orbit, the lower jaw is deep,its ramus ascending almost perpendicu-larly, and the coronoid process is shortand feeble. Their cranium is large, andexpanded laterally, the frontals are earlyanchylosed, the parietals are arched andsmooth, the temporal fossae are small, andthe zygomatic arch is feeble and depressed.

Their transverse occipital ridge is strong-ly marked, and their occipital foramen isplaced far forwards under the base ofthe skull. The frontal extends back-wards, in an angular form, to the sa-

gittal suture, the parietals are small andthrown back, so that the great ala of thesphenoid does not reach them, as it doeseven in the lemurs, and is bounded aboveby the frontal and the temporal bones.The occipital is small, flat, and almostconfined to a basilar aspect. This largehead i3 chiefly composed of the bones ofthe face, from the sphenoid to the inter-maxillaries, and especially of the jaws, forthe reception of very large teeth. Theinfra-orbitary foramen, you observe, ishere subdivided into numerous apertures,as we frequently find it in higher quadru-mana, and, as in most other genera, thereis no distinct supra-orbitary foramen.The intermaxillary bones, of which you

see no trace in these adult human skulls,we have thus traced as constant and se-

parate elements of the cranial vertebrae,

from the osseous fishes to the higher qua.drumanous mammalia, and comparing thehuman adult skull with that of the infe-rior vertebrata, we might suppose that itwas formed in this part upon a differentplan. But all comparisons in organicforms and structures, made with a view totrace resemblances, are to be institutedonly between objects naturally allied. Thelinks that connect the facial bones of thehuman skull with those of the gibbons,the baboons, and the lower quadrumana,are to be looked for in the orangs of Indiaand Africa, and in the lowest of the ne-gro race, where the facial angle and theforms of the several bones of the face andcranium approach, and the general pro.portions of the whole body. The animalcalled ,the chimpanze (troglodytes niger),the black orang, inhabiting, in troops, thewoody plains of Congo and Angola,-ananimal erect, with broad shoulders, a widepelvis, short arms, a prominent nose andheel, and human-like proportions in everypart,—walking with a staff, defending it-self by blows with stones and staves,-forming for itself a little hut, which issafe in the recesses of the forests,-seizingthe negresses and carrying them to thewoods, treating them, it is said, withkindness, and capable, as we know, of ahigh degree of physical education. It isan animal which cannot speak, but ex-

presses its meaning by gestures and

grimaces-capable of being taught to useinstruments and utensils of different kinds,to spread and make its bed to reposeitself upon it,- covering its body, it is said,with leaves, and forming acquaintanceor attachments, not with inferior gradesof animals, but associating, by preference,with our species, as appears from theaccounts of the habits of those animalswhich have been brought on board ves-sels. In that animal, and in the long-armed large Indian orang, we find thatthe two intermaxillary bones which youobserve permanently detached in the in-ferior kinds of quadrumana, holding theincisors of the upper jaw, are also anchy-losed with the upper jaw-bone before theiradult state. That is precisely what takesplace with the intermaxillaries in man.We know that man has the intermaxillarybones at an early period ; and I have oc-casionally seen those bones, with theirsutures, retained in the human skull to a

pretty advanced period, detached from thesuperior maxillaries.The nasal bones become more promi-

nent above the general level of the face,as we ascend from the cynocephali to thistroglodytes; the jaw-bones became shorter,the ramus and the incisors more perpen.

dicular. There is a fifth tubercle in the

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crown of the posterior molar tooth of thelower jaw in the macacus and tlie smmo-pithecus, which appears as a remnant ofthe sixth molar tooth found in that situa-tion in the simiac of America. It marksan inferiority of type, no simiæ of Ame-rica approaching near to the orangs, oreven to the gibbons of the old continent.The kind of motion of the jaws in

bruising and masticating the succulentfruits on which those higher quadruma-nous animals chiefly subsist, requires thatthere should be a considerable extent of Imotion laterally, as well as upwards anddownwards. On that account we observethat the condyle of the lower jaw is flat.The coronoid process ascends but a short

way through the zygomatic arch,-the pro-cess which we saw so prominent and longin ruminating quadrupeds, which movetheir jaw also from side to side. The

glenoid cavity of the temporal bone forthe reception of that condyle has, as youperceive, a fiat surface, so that it has thefreest motion with the inter-articular car-

tilage, to move laterally. This is the more

necessary, on account of the use whichthose duatlrnmanous animals make of thelarge sac or pouch seen on the sides of thecheck. They use that pouch for contain-ing quantities of food which they collect,and which they do not require or desireimmediately to digest, or are not able tocontain at the time in the stomach,serving then the office of a paunch to con-tain the food, until they are ready to mas-ticate it, and also partially to soften it, andto take it when hunger or conveniencerequires.

Ttius, then, you observe, that the OCCI-

pital bone in the higher simiæ rests uponthe atlas and upon the vertebral column,in a position more near to the centre ofthe base of the skull. In the anterior partof the skull vou observe in most of those

quadrumanous animals no trace of the

supra-orbital foramen, the frontal nerveand artery coming generally over the mar-gin of the orbit, or through a notch, as weoften see in man. The turbinated bonesare small, and correspond with the shortand small flat nose; but the ethmoid platespresent a considerable surface for the ol-factory nerves. The body of the sphenoidgenerally remains divided transversely inthe sella tursica, to an advanced period ofdevelopment, being the natural separa-tion of the bodies of two distinct cranialvertebræ.

In the cervical vertebrae we observe,that in place of those bifurcated spinousprocesses which you know to charac-terize the cervical vertebraf of man, theseprocesses here terminate in a sharp singlespine, so far differing from those of the hu-

man skeleton, as you observe in this monamonkey (cercopithecus mona, Fig. 116; .

There is considerable strength and mobilityof the neck, for the motions of the heavyhead. In the vertebral column we observea near approach to man in the numbersand forms of the dorsal vertebrae. Thelumbar vertebrae are generally more nu-merous, and have greater mobility thanin the human body. Those additionallumbar vertebrae appear to be formed

partly at the expense of the sacrum. Theypresent the transverse processes gene-rally much more directed upwards to.wards the head, than you observe in thecorresponding transverse processes of thehuman skeleton; so that the muscles arestrengthened which are attached to them,and which pass downwards. The coccy-geal vertebræ of the quadrumanous animalsare, for the most part, prolonged muchbeyond the extremity of the trunk, form-ing a long moveable tail. That, in am-

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mals which are organized to climb upontrees, is, for the most part, an importantorgan of prehension. We see, particu-larly in the simiæ of America, that this

organ is much developed, and forms inthattribe what is called a prehensile tail-a tail which is muscular and flexible, andis not furred over upon all its lower sur-face, but is provided often with a tough,callous, thick epidermis, which is ca.

pable of firmly holding objects when thetail is twined around them, and pos-sessing at the same time great sensi-

bility like a hand. This we do not meetwith in the old world, where the tails ojthe quadrumana are covered over withfur. The true prehensile organ is peculiarto America. In the coccygeal vertel)rxwe observe that where they are most em-ployed for prehension, their number,their mobility, and the security of theiiarticulations, are increased ; that where

they are not employed as an organ tcassist in climbing, or for the suspensionof the body, the bodies of those vertebraare much more lengthened and cylin.drical.These quadrupeds, climbing and living

upon trees, require to possess great powerand extent of motion in the whole arms, vand, at the same time, great security inthe articulations. The security you per-ceive to be necessary, from the violentexertions they put the arms to. You ob-serve these long-armed gibbons and spider-monkeys, bounding and springing frombranch to branch, and tree to tree, whenpursued, or in their gambols, for the simiaeare naturally lively, active, playful, lasci-vious, and often disgusting animals, fromtheir so perfectly caricaturing the humanform, expression, and action. They bur-lesque our species by their forms, ges.tures, and grimaces, as we have alreadyseen a burlesque upon those compara-tively elevated animals, in the slow-creep-ing, long-armed, tree-climbing sloths. Nowthose violent efforts on the trees, wherethey are seen to throw themselves fromone tree to another, to grasp the brancheswith their hands, and to come down withtheir whole weight on the arm, then witha bound to force themselves up again to ahigher branch-we see that for such strongmotions, and for such active exertions ofthe whole body, great lightness in thebones, and great security in the articula-tions, both of the trunk and extremities,are required, and great flexibility and ex-tent of motion in all their parts. Thus wefind in all these quadrumana the claviclesare strong and human-like in their curvedsigmoid form. It has already, in most ofthe species, that sigmoid curvature whichis so marked in the human clavicle, and I

from which that bone has received itsname. The scapula has also, from the

similarity of the uses to which the anteriorextremities are applied, a form corre-

sponding much with the form of the humanscapula, having an extensive surface bothabove and below the very elevated spine,and, consequently, an extensive margintowards the vertebral column ; hut stillthis bone is longer and narrower than thehuman. The glenoid cavity is compara-! tively deep, and the coracoid and acro-mion processes are large in these quadru-manous animals, so that the head of thehumerus plays upon its cavity with secu-rity. The scapula is most human-like inthe orangs. The sternum of the quadru-mana is observed to present, in the lowestforms of makis and lemurs, an approachtowards the narrow compressed form ofthat bone, so common in inferior ordersof quadrupeds; but in the simix;, and es-pecially in the orangs, it is depressed frombefore backwards, presenting the ex-

panded and flat form which it has in man.The sides of its elements appear some-

times to remain separate through life inthe pitheci. In the adult pongo of theHunterian museum, the sternum is com-posed of a double row of pieces, but in theadult pongo of the Paris museum, there isa single row of four pieces, and the xiphoidcartilage.

In the humerus we perceive the formto approach somewhat to the human, butit is generally more arched, with its

convexity forwards at the upper part.The radius and the ulna are long andslender, and constantly separated, toadmit of the freest pronation and supi-nation. The bones of the carpus are

frequently nine in number, there beingfive in the second row, making one addi-tional to the number found in the humanwrist, where there are only four in each ofthe two rows. It appears that the divisionof one of the ordinary bones, to give greatermobility to the wrist here, gives rise to theninth bone. Flexibility for prehension isof the greatest importance to be preserved,both at the termination of the arms andlegs of quadrumana, that, like a whip,they may twine round the branches, andthen with a firm muscular force securethe grasp which they have obtained;therefore it is that we find the wrist sosubdivided in the quadrumana. Thehands present the same number of bonesas the human in the metacarpus, and inthe phalanges of the fingers, which are alllong, slender bones, except the last pha-langes which support the flat nails of thesimiae. The thumb is never so much de-

veloped, or so opposable, in the quadru-I mana as in the human hands. In all the

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quadrumana of the old world, the thumbis distinctly observed projecting from theinteguments ; but in the genus ateles of thenew world we see onlv a small rudiment-!a tubercle projecting from the inner side ofthe hand, and sometimes not a trace of athumb projecting from the integuments,’although its bones are present beneaththe’ skin of the hand. !

ln the region of the pelvis you observea I’l’lnark2.hle difference in the inferior!

genera of quadrumana, when comparedwith the pelvis of the human body, andthat this depends chiefly upon the nar-rowness of the pelvis, and the lengtheningof the iliac bones; that is accompaniedwith a lengthening of the glutei muscles,the extensors of the femur; for we mustlook to this structure of the bones withrelation to the living movements, to the!active instruments of the rapid and power-ful movememts of those animals. The!lengthening of the glutei muscles, like thelengthening of the muscles attached to the ihead of the humerus, has the effect, fromtheir mode of insertion, of n-toring the bonesto which those muscles are attached througha greater space in a given time. It in-creases the velocity of the motion, whileit loses in strength. The expanded formof those iliac bones in the human speciesis for the insertions of an immense num-ber of separate fibres, short and strong, ofthe glutei muscles. Those very powerfulextensors are required to keep the wholetrunk of the human species upright on thelegs when walking or standing. But that Iis not the use to which the glutei musclesare applied in the quadrumana; in themthey are applied for those bounding andleaping movements which they performwith their posterior extremities, whichare not in them mere pillars of support,but organs of prehension, formed likearms with hands. The sacrum most fre-

quentlyconsistsof three vertebrae. Thecoc-cyx of the orang consists of four as in man.The iliac bones in the orangs are short and

expanded, tlat outwards from the sides ofthe sacrum. The sacro-iliac articulationand the whole pelvis are placed in a lon-gitudinal direction. The tuberosity of theischium is bent outwards and backwards,projecting laterally to a great extent, andis a part of great thickness and breadthin most quadrumana below the orangs.That is the part which the quadrumanousanimals employ to rest the whole trunkupon in a state of repose. It is coveredin the living state with a thick, very dense,cartilaginous mass, called the callosities ofthe nates. Those callosities are not co-vered with hair, but are dense cartila-ginous masses, covering these broad tu-berosities of the ischium. The skin ad-

( heres firmly to those cartilaginous masses,and they adhere most firmly to the ttibe-rosity of that bone. This broad base,! fOrJlIed by the projection of the two ex-

panded tuberosities of the ischium, is thatupon which the quadrumanous animals’ repose themselves in feeding, in sleeping,in rearing their young, or in doing any! acts while their trunk is in a state of

!repose.The femur differ- from the human femur,i being, like the humerus, bent more for-wards, and in having the neck of the boneshorter, and passing out more at right’ angles to the body of the bone. The tro-

chanter 2;zajo?,, you perceive, is by this

raised much higher than the head of thefemur. This trochanter is a part of greatimportance in the active motions of these

! quadrupeds. The tibia and fibula are

’long and slender, widely detached, and’admit of greater extent of movement on; each other than in the human leg, to al-

low the foot to be employed as a hand.From the uses to which the legs ofquadrumanous animals are applied, weperceive that it is necessary that the cal-caneum should project much less than inthe human foot. Were the calcaneum to

; project as much backwards as in the hu-man foot, it might serve the quadrumanousanimal better as a mere organ of support,but it would prevent that motion of ex-tension which is necessary in the footas an organ for seizing or graspingobjects. At the lower end of the

tibia and fibula, which are both stronglyconnected with the tarsus, the astra-

galus has a peculiar oblique twist out-wards, which is increased by the formof the calcaneum, and which obliquity iscommunicated through the scaphoid, thecuboid, and the three cuneiform bones,to the metatarsus, so that by resting thus

! on the outer margin of the tarsus andmetatarsus, the foot has assumed a posi-tion very different from that of the humanfoot, and very ditferent from that in which you perceive the feet ’placed in some ofthe skeletons before you, which are placedin an unnatural position, with the planta, of the feet resting on the ground as inman. The quadrumanous animals, eventhe most elevated species, seldom apply theentire planta of the foot to the ground,but they apply only the outer margin ofthe foot to the earth. By thus apply-ing the outside of the foot to the ground(when these animals are resting upon thefoot), the thumb or inner toe is free, and’ attached in a very oblique manner to the’ internal cuneiform bone, which is here

placed much below the others; it is free,and opposable to the other more length- ened toes of the foot; so that the foot is

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by this mechanism constructed like a longprehensile hand. They can thus use thefoot for standing or walking, while at thesame time it grasps firmly an object withthe thumb or the toes, the outer part onlyof the foot being then applied to the ground.But here, in London, I have seen the liv-ing chimpanze, the black orang of Africa,spontaneously apply the whole planta ofthe foot to the ground in walking; some-times it did and sometimes not; but theorang of India, which was alive beside it,never did,-it applied always the outsideof the little toe to the ground in walking.Twisting the foot of the monkeys out-wards to be applied flat to the ground, inthe manner of the human foot, is an act

painful to them ; those animals, therefore,do not spontaneously assume that attitude,although we daily see that by torture theycan be made to stand in any position. Thefoot of the quadrumana has the samenumber of bones in the tarsus, metatar-sus, and toes, as are found in the humanfoot.

MAN forms alone the highest order ofthe highest class of the animal kingdom,and the highest form of organizationwhich has yet been developed on this

planet, and it is by tracing his organs up-wards, from the monad, through all theirphases of development and their variousmetamorphoses, that we come to perceiveand to comprehend the nature of thepeculiarities which distinguish his struc-ture, his functions, and his form. Withoutthe inferior grades of organization to in-terpret the more complex, that of manwould for ever remain an impenetrablemystery, and the light which is thrownupon the highest is reflected back uponthe lowest by the increased interest thusattached to their study. The whole organ-ization of man is adapted for the erectposition of the trunk, by which his ante-rior extremities are left free for variousemployments, and his head, raised to aheight above the ground, has the principalorgans of the senses directed forwards.

By the great development of his cere-bral organs, the cranium (Fig. 117) is

large, and the organs of the senses beingconfined to a narrow space, the face issmall, and is nearly straight from thefrontal bone to the chin, from the slightprojection of the muzzle, excepting in thenegro, where the projection of the jawsand teeth, and the receding of the frontalbone, reduce the facial angle more nearto that of the orangs. The occipital fora-men and the two occipital condyles areadvanced further forwards on the base ofthe skull than in any of the quadrumana,

I so that his head is nearly poised by thecentre of its base on the atlas, and on the3 perpendicular vertebral column. His fore-- head, his nasal bones, and his chin, pro-t ject more than in any of the quadrumana,the incisors are more nearly perpendicu-lar, the canini shorter, and the tuberclest of the molares more rounded. The squa-1 mous portion of the temporal bone, the

great ala of the sphenoid, and the supe-- rior portion of the occipital, are large; thes temporal fossa, the zygoma, and the coro-; noid process of the lower javr, are small;s the ramus of the lower jaw is larger, and; forms a more acute angle with the base,t than in the last order of quadrupeds; thecondyle of the lower jaw is more elevated3 and convex, and the glenoid cavity for its1 reception is deeper. The nasal process ofr the superior maxillary and the lachrymal- bone pass more into the orbit, and theorbits are more parallel in their direction,f which gives greater precision to all his, visual impressions.

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His vertebral column has a greater sig-moid curvature, the cervical vertebraehave their spinous processes more broad,short, and bifurcated ; the transverse pro-cesses of the lumbar vertebrae extendmore at right angles from the bodies, thesacrum is longer, broader, and more

arched, and the coccyx is comparativelysmall. The ribs are more convex, thesternum is more short and broad, the cla-vicles are more curved and strong, and thescapula is more short and broad, than inthe former animals. The glenoid cavity ofthe scapula is more lateral in its direc-tion, the humerus, with a large articularrounded head, is more straight, the ole-cranon of the ulna comparatively short, andthe bones of the thumb are more length-ened, and more opposable to the otherfingers.The pelvis is shorter and broader than

in the qnadrumana, the iliac bones are moreexpanded and convex, more extended overthe acetabulum, and with a longer crest;the tuberosity of the ischium is less pro-minent, and the symphysis pubis is shorter.The femora are thrown to a greater dis-tance from each other, their head has aless extensive articular surface, their cer-vix is longer and more oblique, and theirtrochauter major less elevated. The legs,thus removed from each other, afford a

broad and secure base of support for theerect trunk, and this is increased by theplantigrade position of the feet, the pa-rallelism and magnitude of the inner toe,- the advanced position of the astragalus,the extension backwards of the calca-neum, the fixed condition of the tarsus,and the strength of the metatarsus andthe bones nf t.hp tnpq-

These peculiarities, however, in theskeleton of our species, are not equally de-veloped in all the races, for the negro hasthe forehead low, the nasal bones less pro-minent, the nose flat and broad, the muzzleprojecting, the incisors inclined forwards,the cranium proportionally small, and thefacial angle often below seventy degrees.Even the Mongolians, with a more ele-vated facial angle of seventy-five degrees,have the nose sunk, the orbits remote, andthe malar hones prominent. It is in the

European race, where the facial angle isabove eighty degrees, that we find all thecharacters of the skeleton the most remotefrom those of the orangs, and from thoseof all the inferior animals.From the adaptation of all parts of the

skeleton of the quadrumana for the in-clined position of the trunk, and of manfor the erect position, their hones are

more easily recognised than those of mostother animals, yet not a fragment of eitherhas ever been found in a perfectly fossil-

ized condition. The bones of quadrumana.occur abundantly in the recent alluvialdeposits along the banks of great rivers intropical countries, but of species now liv-ing in those countries. The bones of our

species have often been found in doubtfulsituations, as in deserted mines, in recentdeposits lying in diluvial caves, in the fis-sures of ancient rocks, in drifted calca-reous sands consolidating on sea-coasts, orcovered with corals at the bottom of thesea, like this specimen of the tibia coveredwith monticulariæ. Skeletons of our spe-cies nearly entire (Fig. 118) are often

found embedded in a solid concretion ofcomminuted shells and corals now form-ing along the coasts at Guadaloupe. Theseskeletons still retain the animal matter ofthe bones; the embedding particles of theshells and corals retain their colouringmatter, and belong to the common spe-cies of those coasts.

Now these are all the observations wehave leisure to make on the solid parts of

! animals-the organs of support. And we. have seen that nature, in the constructionof those solid parts throughout the verte-

, brated classes, has kept with remarkablel, constancy to that typical plan which wasi commenced in the cephalopods by thedevelopment of the laminae of the velie-brae. Since the cartilaginous skeletons ofthe lowest fishes, we have seen that na-ture has directed the currents of nutritiousmatter, conveying the phosphate of lime

with other earths, to certain definite points;that those points have remained remark-i ably constant in their position, whetherthey were afterwards to be anchylosed to-

t gether, or to remain permanently de-r tached-that the centres of ossification- remained the same. BB’e seek, therefore,

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for the theory of this constancy in theplan upon which the skeletons of verte-brated animals are constructed, in the dis-tribution of the nutritious arteries of thebones. In the stages of developmentof the most perfect skeletons of the ver-tebrata, we perceive but a repetition ofthe stages we passed through since wecommenced with the cartilaginous fishes.The earthy matter that is employed inthis great division of the animal king-dom to consolidate the organs of support,is not the same as that which was em-

ployed to consolidate those heavy massivecoverings that were thrown for protectionover the bodies of molluscous and inferioranimals. A much denser material, the

phosphate of lime, is here employed to sup-port the great, elevated, durable fabrics ofthese large animals. But whatever formsthese earthy materials may assume, andwhether placed in the interior of the softparts or on their surface, they are still dueto the living processes of the system, andare permeated by animal matter ; they arenormal parts of the structure, intimatelyconnected with the soft parts, and influ-enced by their contact, and they serve

alike to give form, protection, and support,to the whole fabric.

REMARKS ON

DELIRIUM TREMENS,ITS COMPLICATIONS AND TREATMENT.

By P. BENNETT LUCAS, Esq., Surgeon,London.

THis most interesting and singular dis-ease has within the last few years attractedin an especial manner the attention of theprofession, and many valuable papershave been dedicated to its considerationin the several medical periodicals. Uponits distinguishing characters all are agreed,but upon the pathology of the affection,and the manner of treating it, a similarunity of sentiment does not exist, and thisis the more to be regretted, in consequenceof the remedies proposed for its cure

being very opposite in their effects. When,for instance, we find some practitionersrecommending bleeding, and others vio-lently opposing the use of the lancet underany circumstances ; when we find opiumrecommended, from a moderate to whatmay be termed an immoderate dose ;when the habitual stimulus is liberallysupplied on the one hand, and as unce-remoniously dismissed upon the other;when restraint is considered as taking

away one out of the few chances we haveof our patient’s recovery, and a strait-waistcoat is resorted to with henefit; when,in short, we read of decided success statedto attend very opposite modes of treat.ment,-either the disease must have pre-sented itself under very different aspects,or circumstances must have occurred tocall for other remedies besides those

’ usually recommended.I A practitioner, for the first time, recog-nising the disease, and referring to hislibrary for some practical information,would, in consequence of these differencesof opinion, feel at least undecided iN hatcourse to pursue, and did not his own

judgment direct the administration of hisremedies, he would, in all probability, havelittle reason to congratulate himself for

relying upon the indiscriminate recoiti-mendation he fixed on, and so scrupu-lously adhered to.Did delirium tremens always present

itself in its simple uncomplicated form, itstreatment would be reduced within a verysmall compass, and a sound sleep being itsnatural cure, all our remedies would bedirected to the attainment of that salutaryend. But unfortunately this is not thecase. In some instances the membranes ofthe brain are actively inflamed ; in othersthe chest is engaged; in others the stomachand bowels; and it is very seldom indeedthat the disease is met with, except incomplication with some local or consti-tutional affection, demanding the omissionof remedies considered by some as specifics,and the administration of others very op-posite in their characters. The constitu-tion of the patient, the manner in whichthe disease was induced, and previoushabits, will, in general, render the diseasemore or less manageable, and will influencethe determination to various organs. Inthe habitual tippler, who lives only in ex-citement, and who solicits the disease byan excess of devotion to his accustomedidol, the stomach and bowels will be theorgans found most often implicated; sucha patient having, in addition to the cha-racteristic symptoms, nausea, vomiting,pain in the epigastrium, and scanty, slimy,dejections. Under other circumstances,from hereditary predisposition and dissi-pation, the lungs become the organs en-gaged ; and in one instance of this kindwhich came under my observation, thepatient, after recovering from the disease,died in three weeks of confirmed phthisis.In other cases, a few hours after the dis-ease shows itself, the pulse becomes quick,and loses its soft beat ; the pupils becomecontracted, the eye suffused, the face

flushed; the patient gets violent, but is