. On the anatomy of vertebrates [electronic resource] . B Spermatozoa within theA. Spermatozoa of B. Spermatozoon of sperm-cell {Torpedo Narce). Seymnus nicceensis. cccvi. Torpedo Narce. cccvi. cccvi. is straight, and tapers at both ends: in Seymnus nicceensis, , it is spirally disposed. In Spinax acanthias, the Rays andTorpedos, fig. 404, the spiral coils are rather closer, usually fourin number: in Raia oxyrhynchus the coils are more numerous,but only affect the anterior half of the body. In the Plagiostomes the spermatoa appear as one or more nucleiwithin the sperm-cell, like those i
. On the anatomy of vertebrates [electronic resource] . B Spermatozoa within theA. Spermatozoa of B. Spermatozoon of sperm-cell {Torpedo Narce). Seymnus nicceensis. cccvi. Torpedo Narce. cccvi. cccvi. is straight, and tapers at both ends: in Seymnus nicceensis, , it is spirally disposed. In Spinax acanthias, the Rays andTorpedos, fig. 404, the spiral coils are rather closer, usually fourin number: in Raia oxyrhynchus the coils are more numerous,but only affect the anterior half of the body. In the Plagiostomes the spermatoa appear as one or more nucleiwithin the sperm-cell, like those in fig. 399, b: but they are not,as in Osseous Fishes, excluded in that In each spermatoon1 cccvi. vol. iv. p. 484. SEMINATION OF HJEMATOCRYA. 591 At this stage 406. a spermatozoon is developed, which escapes by solution of thespermatoal wall into the sperm-cell, as in fig. body does not show the spiral the sperm-cell has contained numerousspermatoa, the resulting spermatozoa groupthemselves into a bundle, as in fig. 406 : theirbodies are contiguous and acquire the spiral formbefore escaping from the dilated sperm-cell. The spermatozoa are developed in mostBatrachia as they are in the Plagiostomi; asperm-cell may contain from ten to twentyspermatoa, in each of which the spermatozoonis developed, as in fig. 407, and through solu-tion of the spermatoal membrane the sperma-tozoa become free in the cavity of the sperm-cell, where they usually aggregate into a bundle, pressing the sperm-cell into a pear-shape, which bursts at its small end, and liberateseither the filamentary appendages, as in the Frog, or the spiralbodies, as in Pelohates: in either case the remains of thesperm-cell continue recognisable, for some time, at theno
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