Page:Natural History Review (1861).djvu/486

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474
ORIGINAL ARTICLES.

a long, delicate tube connects each with the chamber containing the genital organ.

The genital chamber contains only the genital organ, whether ovary or testis, which is attached to the anterior wall of the chamber; the wall being reflected over the organ, as is clearly seen at the point of attachment. The membranous wall, however, very soon becomes so completely incorporated with the organ as to be no longer demonstrable. In the female, there are two ovarian outlets from this chamber, as well as the two already noticed as communicating with the small lateral chambers. In the male, there are three outlets only, two leading to the same small lateral chambers, and one into the vas deferens.

Thus it appears that all these so-called aquiferous chambers open externally, through the nipple-formed orifices situated in the branchial chamber. But, as might be expected, they have no direct communication with the blood system; at least, I have hitherto failed to discover any.

In the Loliginidæ we find these chambers considerably modified, and reduced to two in number, — the renal and genital. The former is no longer divided into two by a longitudinal median septum, but forms one large continuous cavity — the pericardial of most writers ; though it never contains the heart, so far as I have observed. In this group, however, it holds, in addition to the vense cavse and their glandular appendages, the hepatic ducts, with their attached pancreatic glands. This is the case in Loligo sagittata, L. media, Onychoteuthis Lichtensteinii, Sepia officinalis, Sepiola Rondeletii, and Ommastrephes todariis. In this last, the lower portion of the intestine and the greater part of the ink-bag, and in Sepia, one half of the stomach and the whole of the spiral cæcum, are also lodged within this chamber. And, in all the species, a small portion of the branchial hearts likewise protrudes a little into it. The nipples, which bring this chamber into communication with the branchial chamber, are placed further forward than in the Octopodidæ.

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.

All these organs are covered with the membrane forming the wall of the chamber, which is reflected over them in the manner of a peritoneum; but it is not easily demonstrable, except at the points where the various organs are attached to the wall, and there it is always seen doubling back upon them. It is thus distinctly visible on the stomach, over which it passes backwards, forming a fold carrying the