. The cyclopædia of anatomy and physiology. Anatomy; Physiology; Zoology. Female organs of the Maja Squinado. The ovaries in the Decapoda brachyura resem- ble four cylindrical tubes («, b,Jig. 434) placed longitudinally in the thorax, and divided into two° symmetrical pairs, each opening into a distinct oviduct, yet communicating with one another by a transverse canal («'), and by the intimate union of the two posterior tubes in a portion of their length (//). The ovi- ducts, ns well as the ovaries, are of a whitish colour; they are short, and become united in their course to a kind of sac (c)
. The cyclopædia of anatomy and physiology. Anatomy; Physiology; Zoology. Female organs of the Maja Squinado. The ovaries in the Decapoda brachyura resem- ble four cylindrical tubes («, b,Jig. 434) placed longitudinally in the thorax, and divided into two° symmetrical pairs, each opening into a distinct oviduct, yet communicating with one another by a transverse canal («'), and by the intimate union of the two posterior tubes in a portion of their length (//). The ovi- ducts, ns well as the ovaries, are of a whitish colour; they are short, and become united in their course to a kind of sac (c), the neck of which extends to the exterior of the ani- mal's body (of); there is one of these on each side, and they are known by the name of the copulatory pouches. It is into these reser- voirs that the male pours the fecundating fluid, which is here stored up and applied to the ova as they pass in succession along and out of the oviducts. These after a course, which is never long, terminate at the vulvse, openings formed in the sternal pieces of the segment which supports the third pair of ambulatory extremities. The Anomoura and Macroura have no copu- latory pouches, and their vulvse are situated on the basilar joint of the ambulatory ex- tremities of the third pair. The mode in which fecundation is accomplished in these genera is consequently much less apparent than in the Brachyura. Many writers are of opinion that this operation takes place in the interior of the ovaries, a process that appears by no means feasible on account of the inequality of development of the ova, which is such, that the last of them are not in being even long after the first have been ex- pelled. It would perhaps be more correct to suppose that fecundation does not take place till after the ova are laid, which we know to be the case among the Batrachia and the greater number of Fishes. The female Crustacean does not abandon her eggs after their extrusion. Those of the Deca- pods preserve them
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