Elements of comparative anatomy (1878) Elements of comparative anatomy elementsofcompar00gege Year: 1878 GENERATIVE ORGANS OF AETHROPODA. â 2'J'J The arrangements in the Pycnogonida are just as peculiar; their generative products are formed on the wall of the coeloni, and are. passed out by special orifices (which are sometimes found on all, and sometimes on only one pair, of the feet). This character reminds us of the lower arrangements seen in the Annulata. The conversion of appendages into copulatory organs, which obtains in the Crustacea, is seen in the Aranea only from among the Arachnid
Elements of comparative anatomy (1878) Elements of comparative anatomy elementsofcompar00gege Year: 1878 GENERATIVE ORGANS OF AETHROPODA. â 2'J'J The arrangements in the Pycnogonida are just as peculiar; their generative products are formed on the wall of the coeloni, and are. passed out by special orifices (which are sometimes found on all, and sometimes on only one pair, of the feet). This character reminds us of the lower arrangements seen in the Annulata. The conversion of appendages into copulatory organs, which obtains in the Crustacea, is seen in the Aranea only from among the Arachnida; in the males of this order the palpi are organs of a complicated structure, which convey the sperm to the female generative orifice. § 232. The generative organs of the Myriapoda are, in their form and arrangements, most similar to those of the Arachnida, and, as in these forms, they sometimes open far forwards on the body, namely, on the third segment of it. The genera- tive organs of the Scolopendrida3 are placed in the hinder end of the body. In the females the generative glands are either simple externally and form an elongated tube, on the inner surface of which the ova form projections (Julidas, Scolopen- dridse, and Glomeridas), or they are double (Cras- pedosoma), in which case they are united at their anterior ends, while the oviducts open separately. In the Scolopendridas the simple ovarian tube is, as a rule, continued on by a simple oviduct; but the double character of these organs is implied in the development of ova on both sides of the ovarian tube. The accessory organs are formed by two pairs of bodies, which sometimes open into the ovi- duct, but ordinarily directly into the genital orifice; they partly form cement glands, and partly receptacula seminis. The male organs also are often double in their efferent ducts and accessory parts only. However, mauy Glomeridas and Julidas are provided with a double testicular tube, which passes into a common vas def
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