. Elements of comparative anatomy. Anatomy, Comparative. GENERATIVE ORGANS OE ARTHROPODA. •>•>; •J 5 a ceecal uterus which is continuous with the duct. At their hinder end they seud off a short duct (od) to the generative pore. The organs of either side are united in the same way in the testis. This is formed of a double row of glandular follicles, which unite into a coiled canal, which forms the simple excretory duct and opens at the base of the last pair of feet. The generative organs of the Decapoda resemble those of Mysis, by being similarly connected in the middle line; they appear
. Elements of comparative anatomy. Anatomy, Comparative. GENERATIVE ORGANS OE ARTHROPODA. •>•>; •J 5 a ceecal uterus which is continuous with the duct. At their hinder end they seud off a short duct (od) to the generative pore. The organs of either side are united in the same way in the testis. This is formed of a double row of glandular follicles, which unite into a coiled canal, which forms the simple excretory duct and opens at the base of the last pair of feet. The generative organs of the Decapoda resemble those of Mysis, by being similarly connected in the middle line; they appear to be further developed by various differentiations. The female A organs are formed by two long tubes which run for- wards and backwards, and are united transversely with one another; these tubes function partly as germinal glands, but chiefly as ovi- duct and uterus. In the Crayfish the two anterior divisions have the form of short lobes, while the two hinder ones are fused into an unpaired piece. On each side a short duct passes to the genital pore, which in the Caridina has the same position as in the Schizo- poda; in the Macrura it is placed on the basal joints of the third pair of feet, but in the Brachyura on the segment of the body, which carries this pair. The Brachyura are also distinguished by a pouch-like enlargement of the oviduct (seminal pouch). In the male appai'atus the testes are formed by two much-coiled tubes, which are transversely connected with one another in front, and which, like the female organs, lie for the most part in the cephalo- thorax; in Pagurus only are they placed in the abdomen. In the latter they give off two long and closely-coiled but gradually-widen- ing ducts. Herein they agree with most of the Decapoda, but they are distinguished from them partly by the increased size of the lobes formed by the coils of the seminal canal, and partly also by the formation of the unpaired piece, which unites the glands of either side. The germinal g
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Keywords: ., bookcentury1800, bookdecade1870, booksubjectanatomycomparative
