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from the research group in their relative lack ofectomorphy. In this country TANNER 8 has shownthat officer-cadets at Sandhurst are on-the averagemore mesomorphic and endomorphic than under-

graduates at Oxford, while preclinical studentsat a London hospital were intermediate between theSandhurst and Oxford groups. PARNELL 9 has foundthat at Oxford medical students are more mesomorphicthan the remainder, and that at Birmingham dentaland engineering students are more mesomorphicthan students of physics and chemistry. Moreover,the whole distribution of somatotypes at Oxford ismore central than at American universities studied

by SHELDON. The extreme mesomorphs and theextreme ectomorphic endomorphs were absent fromthe Oxford group, and there is a relative shortageamong them of extreme ectomorphs. These studiesrelate somatotypes to choice of, and selection for,career ; but association with success in career is of

greater practical importance. As a first step PARNELL 11has attempted to relate the somatotypes of Oxfordstudents to the type of degree they achieve in thefinal honours examinations. His numbers are smallbut suggest real differences. Notably there is a

tendency for those predominating in mesomorphy11. Parnell, R. W. Brit. med. J. 1954, ii, 491.

to get their fair share of first-class honours andrelatively few thirds ; the great majority achieveseconds. Understandably this group were also foundto have made the biggest contribution to universitysport. The highest proportion of firsts came fromnear-central endomorphic ectomorphs. These interest.ing findings need confirmation and further analysis;one possible source of confusion is that firsts may beawarded more generously in some, subjects thanothers. There is no reason to suggest that physiqueis in any way related to intelligence, and so somato.type is related to academic success probablythrough temperament. Perhaps the highly intelligentamong extreme ectomorphic endomorphs haveinsufficient energy to get to the university; while

intelligent extreme mesomorphs may prefer to gettheir powerful grip on adult life early without wastingtime on non-vocational education. Perhaps, too,moderately high mesomorphs, if they get to theuniversity, have sufficient drive at least to achievea second, but may be too restless to get a first.The basis of these probable; though not fully

proven, relationships between physique, tempera.ment, and proneness to disease is uncertain. Muchof the association may be basically genetic and dueto the multiple effects of single genes.

Annotations

MALARIA IN THE AMERICAS

THE inception of a five-year campaign to eradicatemalaria from the entire American continent has beenannounced by the Pan-American Sanitary Bureau, asubsidiary of the World Health Organisation. The extentof the undertaking can be judged from the fact that135 million people in the Americas live in potentiallymalarious areas=-60 million in regions where the diseasehas been suppressed, 45 million in " protected " zones,and 30 million in unprotected areas. The aim is to Bextend control to all the malarious regions, and to

intensify it to the point where transmission ceases. Iftransmission can be prevented for a few years gameto-cytes of PlaÚ;wdium falciparum or P. vivax will not recurand the disease will disappear. ,

Twenty years ago -such a scheme would have beenfantastic. But the residual insecticides have made

possible very large and successful antimalarial cam-paigns-for example, in the Mediterranean, in the

U.S.A., and in Ceylon. The highest levels of controlhave been achieved in the more temperate climates,where both the plasmodium and the anopheles are

seasonally checked by cold. Much of the Americanterritory already conquered falls into this category ;whereas it is not unlikely that the areas at present" unprotected " from malaria are tropical, undeveloped,and largely inaccessible. Furthermore, recent events inCentral American States suggest that political unrestmay hamper international operations.

In most previous campaigns there has been only onemain vector to attack. But in the vast Americanterritory many different anophelines predominate in.different regions (e.g., A. f7eebor.fai, A. quadrimaculatus,A. albimanus, A. darlingi, A. (K) bellator, and A. pseudo-punctipennis). The problem of suppressing transmissionis different with each of these mosquitoes. Their verydiverse breeding-habits are probably unimportant, for itis almost certain that they will be attacked in the adultstage by residual insecticides. The most importantcharacters of the insects are : (a) their " domesticity "(i.e., whether they bite man in or near houses and will

rest on treated walls) ; (b) their sensitivity to theinsecticide ; and (c) the possibility of their developinginsecticide-resistant strains. Resistance to insecticidesis a serious hazard for which we must remain alert. InGreece, insecticides gave perfectly satisfactory resultsfor several years ; but last year malaria was transmittedin 144 villages owing to resistant strains of 4. sacharovi.

Malaria eradication, though not so difficult as mosquitoeradication, demands much more effort than malariacontrol. An attempt at complete suppression throughoutsuch a vast area as North and South America will callfor all the optimism and drive traditionally associated

with the New World.

1. Podolsky, M. L., Jester, A. W. J. Pediat. 1954, 45, 633.

INTESTINAL OBSTRUCTION IN THE NEWBORN

AIR is the most useful contrast-medium for the diagnosiscof intestinal obstruction in the newborn infant. It is

ingested with the first breath and passes rapidly fromthe stomach into the small and large bowel. Podolskyand Jester have reinvestigated the rate of passage ofair in a series of normal and premature babies and, asmight be expected, they found considerable variations,Within the first two hours all the babies had air in thesmall bowel, and in 50% it had already passed into thecaecum or ascending colons. By six hours the transverseand descending colon were filled ; but the filling of thesigmoid and rectum was inconstant ; air showed in the

sigmoid in 82% at six hours but in only 25% at eighthours. Podolsky and Jester concluded, reasonablyenough, that flatus must have been passed per rectum,for air reaccumulated over the next few hours. In

premature babies the air tended to progress more rapidly;one infant weighing 4 lb. 8 oz. had air in the rectum twohours and thirty-five minutes after birth.The value of a plain radiograph of the abdomen in

localising intestinal obstruction will therefore dependlargely on the time at which it is taken. Duodenal andhigh-intestinal obstruction may be recognised withina few hours after birth, whereas obstruction lower d01l11the alimentary tract may not be apparent until at leastfive or six hours after birth. Podolsky and Jester remarkon the importance of lateral films, particularly for recog-nising the rectum and sigmoid, since loops of ileum often

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lie below the pelvic brim and on an anteroposterior filmmay be mistaken for the lower bowel. The distributionof gas in the intestine is not the only diagnostic feature ;for the presence of an obstruction will lead not only tofailure of passage of air but also to gaseous distension ofthe bowel, and this gives rise to characteristic appear-ances such as the gross distension of the stomach andfirst part of the duodenum in duodenal atresia. Radio-

graphs must always be taken with the infant upright,except in rectal atresia when the patient must be invertedand a metallic object placed in the perineum so that thegap between the gas-filled lower bowel and the skin maybe estimated. Barium by mouth has no place in theinvestigation of the newborn infant, and it may be

dangerous if there is vomiting. But a barium enema isessential for the diagnosis of low-intestinal obstructiondue to Hirschsprung’s disease, for there is no othermethod of recognising the typical narrow segment.2Surgery of the newborn infant has advanced strikingly

in the past decade, and more accurate diagnosis ofintestinal obstruction by radiography has played nolittle part in this progress.

2. Bodian, M., Stephens, F. D., Ward, B. C. H. Lancet, 1949, i, 6.3. J. Amer. med. Ass. 1954, 156, 1081.4. Ibid, p. 1171.5. Achard, C., Loeper, M. C.R. Soc. Biol. Paris, 1901, 53, 346.6. J. Amer. med. Ass. 1954, 156, 1252.

DIETARY SODIUM RESTRICTION

IN the U.S.A. the value and dangers of dietary sodiumrestriction have been concisely and authoritativelysummarised in excerpts from a report prepared by a smallcommittee for the Food and Nutrition Board of theNational Research Council and the Council on Foods andNutrition. The first excerpt 3 deals with the physiologyof sodium, and the normal response to sodium restriction.The second 4 shows how the indications for sodiumrestriction have been extended since, in 1901, Achard andLoeper 5 first appreciated the connection between saltintake and the formation of cedema in cardiac failure. Inaddition to cardiac failure, the conditions in which sodiumrestriction may be of value are now held to includehypertension, renal disease, cirrhosis of the liver, toxaemiaof pregnancy, and Meniere’s disease. The report is

moderately enthusiastic about restriction of sodium incardiac oedema, oedema relating to cirrhosis, and toxaemia,of pregnancy. The verdict on the value of restriction in

hypertension and Meniere’s disease is " not proven "-

and this carries the stigma which in fact, if not in theory,goes with such a verdict. The dangers of sodium restric-tion as a general treatment for renal disease are empha-sised, in relation to the possibility of " salt-losingnephritis," and the appearance of a low-salt syndrome,with dehydration and a precocious increase in the blood-urea level. The report points out once again that in thetreatment of cedema the restriction of sodium must be

rigorous, with a daily intake not exceeding 500 mg.This requires a considerable effort by the doctor or

dietitian in planning the diet, and a greater effort by thepatient in consuming it ; the labours of both (in America)should be lightened by the requirement of the Food andDrug Administration that foods in such a diet shall belabelled with their sodium content per 100 g. and perserving; and apparently such foods may be had in

variety.Unfortunately painstaking adherence to such a diet

may fail to achieve its objective, and may even lay thepatient open to hazards,6 including inadequate generalnutrition and vitamin deficiencies ; and a greater rangeof low-sodium foods and the administration of vitaminsupplements are recommended. The " sodium-depletionsyndrome" may appear, especially when a low-sodiumdiet is conjoined with mercurial diuretics, or whenclimate or central heating provoke significant sodium

loss in the sweat ; and the report recommends that theserum-sodium level should be checked weekly or even

more often. Loss of responsiveness to mercurials, anddehydration with a rising blood-urea level, may also bedue to excessive sodium restriction.On this side of the Atlantic we are generally less

rigorous in demanding sodium restriction. We try toatone for our shortcomings with mercurial diuretics, orwith cation-exchange resins to bind some of the dietarysodium after it has fulfilled its office of seasoning our food.But occasional patients derive psychological strengthfrom a strict regimen, and it is perhaps in them that weshould look more closely for the harmful side-effects lesslatent in a low-sodium diet.

1. Hare, R., Wildy, P., Billett, F. S., Twort, D. N. J. Hyg., Camb.1952, 50, 295.

2. Wildy, P., Hare, R. J. gen. Microbiol. 1953, 9, 216.3. Thomas, C. G. A., Hare, R. J. clin. Path. 1954, 7, 300.

ANAEROBIC COCCI

ANAEROBIC cocci are common commensals of man, but

they are all sensitive to penicillin and so are not of greatpathological significance today. Formerly, the anaerobeStreptococcus putridus was recognised as an importantcause of a dangerous kind of puerperal infection. This

organism and closely related strains still comprise thecommonest group found in puerperal pyrexia, and theyare probably the cause of other forms of suppuration-for example, anaerobic streptococcal myositis. In the

days before penicillin reduced the pathological significanceof the anaerobic cocci, these organisms were in a sense" unpopular " with bacteriologists. Partly this wasbecause in many laboratories methods for isolatinganaerobes in pure culture were not part of the routine,and partly because critical study often disclosed thatcultures of cocci thought to be obligate anaerobes wereonly facultative anaerobes. But perhaps the chief reasonwhy the anaerobic cocci were not welcomed as objects forstudy and identification was that their taxonomy waschaotic : the most widely accepted scheme of classifica-tion comprised eight genera with thirty-two species andseveral subspecies. Many of the species were so poorlydescribed that their names could not be justified, andsome of the criteria for differentiation of species were soquestionable that the whole picture appeared confusedin any light. Still worse, the biological characters of asingle strain were liable to change unpredictably betweenone laboratory and another and even within a singlelaboratory between one batch of medium and another.

Bacteriologists owe a debt of gratitude to Prof. RonaldHare and his colleagues,1-3 who have done much notonly to bring order into the taxonomy of the anaerobiccocci, both gram-positive and gram-negative, but alsoto explain the reasons for some of the variability in thefermentation and other reactions of these organisms. Itnow appears that the exact composition of the mediumand choice of test substrate is very important : sulphurcompounds are required for gas formation by some strains;fatty acids must be present in the medium to allow otherstrains to show fermentative activity ; and still otherstrains can attack organic acids but not carbohydrates.With media containing peptone, agar, or digest broth,enough of some of these substances may be present asimpurities in some batches and absent from other batchesto account for the hitherto mysterious variability in thereactions of the anaerobic cocci.By methods and in media which they fully describe,

Hare et al. have examined 233 strains of anaerobic cocci.Of these, 141 were commensals isolated from healthypeople-from such situations as the nasopharynx, mouth,skin, intestine, and vagina. The remaining 92 strainscame from material aspirated at bronchoscopy (10 strains),abscesses in lungs removed at operation (3 strains), spu-tum from cases of chronic lung infection (10 strains),the genital tract of cases of puerperal pyrexia (60 strains),