Albany Hancock

“ The heart, in some of the Loliginidæ, 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 Octopodidæ the heart lies in the cellular tissue, between the renal and genital chambers, and is more or less enveloped by the wall of the former : but here, as in the other group, there is no pericardial sac.
The heart itself is strong and muscular, and the fibres are of the striated kind. ”

“ As the glandular appendages of the venæ cavæ are now generally acknowledged to be of a renal nature, the office of the chamber containing them is, apparently, to receive the urine as it la secreted, and then to expel it through the nipple-shaped orifices situated in the branchial chamber. And the genital, which we have seen communicates with the renal chamber, may be looked upon as an extension of the latter; the same membrane undoubtedly forming the walls of both chambers. ”

“ The genital chamber is very much increased in dimensions in this group, occupying the whole of the abdomen from the liver backwards to the end of the tail. It contains, besides the testis or ovary, with the single exception above alluded to, the stomach and cæcum; also the branchial hearts and their appendages, a small portion of the hearts only protruding into the renal chamber, as already noticed. The latter organs are placed in two recesses, situated at the sides towards the anterior end of the cavity, and which communicate freely with the chamber. ”

“ Such fibres assuredly exist, and are most plentiful, lining the inner surface of the cavity, where they form numerous circular meshes of various sizes, bordering the orifices of the channels, that permeate the substance of the organ in all directions. Fibres, also, pass in every direction through the glandular mass of the walls. There can, therefore, be no question as to their being blood-propelling organs, though they are at the same time glandular. ”

“ But we must reserve further remarks on this subject until we have taken a glance at the vascular system.
According to Milne Edwards, the blood system in these animals is incomplete, as it is in all other mollusks. And in proof of this, a large sinus, or lacune, is referred to in the Octopodidæ, which is asserted to be the homologue of the abdominal or visceral chamber usually observed in the Mollusca. This sinus is situated on the dorsal region of the body, and extends nearly the whole length of the animal. ”

“ The deleterious urinary matters are consequently always confined to the renal chamber proper.
Now we have seen that the cardiac appendages are always bathed by this fluid, both externally and internally, however the parts may be modified; that their lining membrane is raised into folds and wrinkles, which are clothed with minute papilla?, thus giving great increase of surface; that the papillæ are filled with granular cells, and are in connexion with a highly vascular parenchyma, and that the trunks of the vessels permeating this parenchyma, open into the branchial hearts. ”

“ In the renal chamber proper this membrane is in part specialized, forming the glandular appendages attached to the venæ cavæ, the blood channels themselves only supplying the vessels that permeate these organs. ”