173 

 XLVIIL— On Certain Points tn tin; Anatomy and Physiology 



OF THE DlBRANCHIATE CEPHALOPODA. By A lkmy I Tin ic< >ck, Esq. 

 [Read at the Meeting of the British Agnation, September, 1861.] 

 I propose, on the present occasion, to give some results at which 

 I have arrived respecting the anatomy ami physiology of the 

 Dibranchiate Cephalopoda; whose structure { ha\'e Been etfgage'd 

 investigating: for some time past. My observations will lie confined 

 almost entirely, to the so-called water system and to the blood 

 system; and on these points I shall speak as concisely as possible, 

 reserving for some future opportunity detailed accounts of them, 

 when I hope to be able to lay before those interested in such sub- 

 jects a memoir treating on the general anatomy of this order of the 

 Cephalopoda. 



First, then, with regard to the so-called water system. In the 

 Octopodidce this consists of five chambers; namely, two large cham- 

 bers, containing the vense cava 1 ; two small lateral ones, which open 

 into the above, and which communicate by long slender tubes with 

 the fifth, the posterior or "genital chamber," which always contains 

 the special genital organ, the ovary or testis, according to the sex. 



The two tirst-mentioned chambers lie along each side of the 

 median line, separated by a membranous partition, and immediately 

 within the abdominal wall. The liver lies in front of, and above, the 

 ovary or testis behind them. Each opens into the branchial chamber 

 by a nipple-shaped orifice placed near to the root of the gill. These 

 two chambers contain the two venas cava?, with their glandular ap- 

 pendages. The convoluted or upper portion of the intestine, and a 

 limited portion of the branchial hearts, also project into these cavities. 

 Over all these organs the membranous wall of the chamber is 

 reflected; but on the glandular appendages of the vena 1 ca\;e if is 

 scarcely, if at all, demonstrable. I shall uniformly designate t liese the 

 " renal chambers," as they always contain the veiwr cava* with their 

 glandular appendages, which latter undoubtedly perform, in whole or 

 in part, the function of a kidney, as is now generally admitted. 



Besides the external nipple-shaped openings already specified, 

 there are other two orifices leading into thv^c chambers. Those 

 orifices are situated in the dorsal wall of the chamber, close to the 

 base of the nipple-shaped oriJices; and establish a communication 

 between the renal chambers and two small, elongated cavities placed 

 between the wall of the former and the lateral walls of the abdomen. 

 These orifices are also somewhat nipple-formed, with the lips opening 

 outwardly, or into the renal chambers, and are placed at ihe anterior 

 extremity of the small chambers ; the other c\t rendu . which is some- 

 what enlarged, abuts upon the branchial heart, and encloses within it 

 the so-called "fleshy appendage - ' aiiached to that blood-propelling 

 organ. The interior of these small chambers is longitudinally and 

 irregularly laminated, with the surface of a glandular appearance, and 



