. Elements of Comparative Anatomy. Fig. 114. Generative organs of an Ophiurid (Opliioderma lougicauda). The dorsal integument and the digestive organs have been removed. ';• Arms, g Ovarian ah-eady seen to occur in the Asteroida. In the aproctous forms the tubes have no excretory orifices, and the genera- tive products are passed into the body- cavity. We do not yet know how they reach the exterior. In other Asteroida the generative glands open to the exterior by special plates, dis- tinguished by their fine pores (cribri- form plates), and placed in the dorsal interradii; or they have
. Elements of Comparative Anatomy. Fig. 114. Generative organs of an Ophiurid (Opliioderma lougicauda). The dorsal integument and the digestive organs have been removed. ';• Arms, g Ovarian ah-eady seen to occur in the Asteroida. In the aproctous forms the tubes have no excretory orifices, and the genera- tive products are passed into the body- cavity. We do not yet know how they reach the exterior. In other Asteroida the generative glands open to the exterior by special plates, dis- tinguished by their fine pores (cribri- form plates), and placed in the dorsal interradii; or they have a single duct with a narrow orifice (Pteraster). Each organ is surrounded by a blood sinus, which envelopes the separate lobes and lobules. The generative products pass into this sinus and are not evacuated directly. The structure and arrangement of the generative organs of the Ophiurida is the same as in the Asteroida. There is only one example of hermaphroditism (Ophiura squamata). The generative glands (Fig. 114, (/) are arranged by pairs in each interradial space, and on the Fig. 115. Transverse section through the pinnula of a sexually mature Comatula (Ajitedon Esch- richti). The dorsal surface is turned upv^ards, and the ventral downwards, 'p Tentacle, g Lumen of the genital chord, w Water- vessel, with lateral branches into the tentacles, n Nerve - chord. h Blood-vessel on it. c g Canal around the genital chord, c d Dorsal, c V Ventral canal. All three com- niunicating with the coelom (after H. Ludwig).. Please note that these images are extracted from scanned page images that may have been digitally enhanced for readability - coloration and appearance of these illustrations may not perfectly resemble the original Gegenbaur, C. (Carl). London : Macmillan
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