482 OKIGIFAL AETICLES. 



chamber, and that consequently we have here a rudimentary form of 

 the lymphatic system. 



This suggestion is to some extent corroborated by the nature of 

 the branchial hearts, into the midst of the glandular walls of which the 

 lymph is apparently thrown, and there probably undergoes some as- 

 similating influence, on its passage into the circulation, like that which 

 is supposed to be exercised by the spleen, and the other glandular ap- 

 pendages in connexion with the lymphatic system of the higher animals. 



It would thus appear that these so-called water chambers form a 

 diffused kidney, having, probably in connexion with it, a rudimentary 

 lymphatic system. It is, however, generally believed that they receive 

 water into their cavities from the exterior ; but it is not easy to con- 

 ceive for what purpose the raw element should be thus admitted to 

 bathe the surfaces of the various delicate organs that lie within these 

 cavities. There is nothing to give colour to such an opinion, except 

 the fact that the renal chamber opens externally ; and yet it would 

 have been rather extraordinary if no such orifice had existed to 

 admit of the escape of the urine. And, moreover, it is evident that 

 this opening, which is, so far as my experience extends, always more 

 or less nipple-formed, is ill calculated for the ingress of fluid, while, 

 on the contrary, it is perfectly adapted for its egress. The same is 

 the case with regard to the passages of communication between the 

 renal chamber and the other portions of this so-called water system. 

 This is most strikingly so in the Loliginidce, in which it would 

 seem impossible for the fluid in the renal, to pass in a backward 

 direction into the genital chamber ; though the passages are most 

 admirably formed to allow the flow of the fluid in the opposite direc- 

 tion, — the tubes connecting the two chambers opening into the renal 

 chamber, much in the same manner as the ureters do into the bladder 

 of the higher animals. 



Neither have I yet been able to satisfy myself of the existence of 

 any water canals, or system of water chambers, opening externally in 

 the neighbourhood of the head or tentacles. Some writers appear to 

 have taken the olfactory openings for orifices leading into such 

 aquiferous passages or chambers, and probably some of the other 

 openings described, are nothing more than mucous pores. But this 

 branch of the subject requires further investigation. 



Before concluding, one or two points of detail may be mentioned 

 in connexion with the vascular system. "With regard to the heart, I 

 can find nothing deserving the name of pericardium. The renal 

 chamber has been so designated ; but, as we have seen that the heart 

 is never placed within it, this is evidently a misnomer. The heart, in 

 some of the Loliginidce, lies within the genital chamber, but is not 

 enclosed in a special receptacle. The membrane, forming the wall of 

 the chamber, is apparently reflected over it, though it is so completely 

 incorporated with the surface of the organ as not to be demonstrable. 

 In the Octopodidce the heart lies in the cellular tissue, between 

 the renal and genital chambers, and is more or less enveloped by the 



