| Summary: | 1. In Parribacus antarcticus and Scyllarus martensii mitotic division of germinal epithelial cells produces primary spermatocytesy whereas in Scyllarides squammosus this function of the germinal epithelium is limited to comparatively few large, oocytelike cells. 2. Metamorphosing spermatids in all three species are expelled from the sacculi of the testis by the rhythmical activity of their germinal epithelium. This probably accounts also for the clumping of the spermatozoa in the collecting tubule; each clump represents the extended contents of a single sacculus. 3. In Scyllarus martensii and Scyllarides squammosus a continuous, cord-like, encapsulated spermatogenic mass traverses the vasa deferentia, whereas in Parribacus antarcticus the spermatogenic mass separates into distinct ampullae which become encapsulated and are further provided with an enveloping sheath. This sheath between adjacent ampullae becomes ribbon-like, twists, and ultimately forms short, doubly twisted peduncles. 4. A secretion of the typhlosole in all three species surrounds the completed spermatophores and forms the homogeneous matrix. 5. Although these three species are anatomically similar, the spermatophores of Scyllarus martensii and Scyllarides squammosus resemble non-pedunculate spermatophores of the palinurids, the astacids, the homarids, and the nephropsids, whereas those of Parribacus antarcticus more nearly resemble the pedunculate spermatophores of certain pagurids. 6. Spermatophoric evidence above does not justify the inference that Parribacus antarcticus occupies a systematic position intermediate between the Macrura and the Anomura.
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