Vol. 79 April 1979

The Journal of

Experimental BiologyEDITED BY

J.E.TREHERNE

WITH W.A. FOSTER & P. K. SCHOFIELD

PACEPic, P., ELLORV, J. C. and Lucu, C. Evidence that K-dependent transport components in

addition to Na-K ATPase are involved in Na and CI excretion in marine teleost gills . iBULLOCH, A. G. M. and DORSETT, D. A. The functional morphology and motor innervation of

the buccal mass of Tritonia hombergi y

BULLOCH, A. G. M. and DORSETT, D. A. The integration of the patterned output of buccalmotoneurones during feeding in Tritonia hombergi . . . . . . . 23

BENTLEY, P. J. and YORIO, Y. Do frogs drink? + i

MCDONALD, D. G., MCMAHON, B. R. and WOOD, C. M. An analysis of acid-base disturbancesin the haemolymph following strenuous activity in the Dungeness crab, Cancer magister 47

NEIL, DOUGLAS M. and SCHONE, HERMANN. Reactions of the spiny lobster Palinurus vtdgaristo substrate tilt. II. Input-output analysis of eyestalk responses 59

BURNS, M. D. and USHERWOOD, P. N. R. The control of walking in Orthoptera II . Motorneurone activity in normal free-walking animals 69

MEISS, DENNIS E. and GOVIND, C. K. Regional differentiation of neuromuscular synapses ina lobster receptor muscle Qq

PACKER, RANDALL K. and SUNKIN, ARTHUR L. Blood acid-base balance in brook trout (Salve-linus fontinalis) t [ 5

PACKER, RANDALL K. Acid-base balance and gas exchange in brook trout (Salvelinus fonti-nalis) exposed to acidic environments . . . . . . . . . 1 2 7

HOLBERT, P. W., BOLAND, E. J. and OLSEN, K. R. The effect of epinephrine and acetylcholineon the distribution of red cells within the gills of the channel catfish (Ictalurus punctatus) 135

LORETZ, CHRISTOPHER L. Water" exchange across fish gills: the significance of tritiated-water flux measurements t^y

BARRERA-MERA, BALTAZAR and BERDEJA-GARCIA, G. YOLANDA. Bilateral effects on retinalshielding pigments during monocular photic stimulation in the crayfish, Procambants . 163

O'SHEA, MICHAEL and EVANS, PETER D. Potentiation of neuromuscular transmission by an"octopaminergic neurone in the locust 169

SATTERLIE, RICHARD A. and CASE, JAMES F. Neurobiology of the gorgonian coelenteratesMuricea californica and Lophogorgia chilensis 191

KUWADA, JOHN Y. and WINE, JEFFREY J. Crayfish escape behaviour: commands for fast move-ment inhibit postural tone and reflexes, and prevent habituation of slow reflexes . 205

RAHAT, M. and MONSELISE, EDNA BEN-IZHAK. Photobiology of the chloroplast hosting molluscElysia timida (Opisthobranchia) . . . . . . . . . . . 225

OKUNO, MAKOTO and HIRAMOTO, YUKIO. Direct measurements of the stiffness of echinoderm

sperm flagella ' 235

WEBB, P. W. Mechanics of escape responses in crayfish (Orconectes virilis) . . . 245

MCMAHON, BRIAN M. and BUROCREN, WARREN W. Respiration and adaptation to the terrestrial

habitat in the land hermit crab Coenobita clypeatus 265BUTLER, P. J. and WOAKES, A. J. Changes in heart rate and respiratory frequency during

natural behaviour of ducks, with particular reference to diving 283

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Printed in Great Britain at the University Press, Cambridge

The Journal of

Experimental Biology

EDITED BYJ. E. TREHERNE

WITH W. A. FOSTER & P. K. SCHOFIELD

VOLUME 791979

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