. The biology of the amphibia. Amphibians. 16 THE BIOLOGY OF THE AMPHIBIA. Fig. 6.—Spermatozoa of various amphibians. A. Desmognathus phoca. B. Bombina bombina (after Retzius). C. Hyla arborea (after Retzius). D. Crypto- branchus alleganiensis (after Smith). , cytoplasmic body. Hynobiidae and Crypto- branchidae, but all higher groups except the specialized Meantes possess a series of tubules in the roof of the female cloaca which retain, for varying periods, the sper- matozoa usually picked up en masse in the form of a sper- matophore (Fig. 7) by the female with her cloacal lips. These tu
. The biology of the amphibia. Amphibians. 16 THE BIOLOGY OF THE AMPHIBIA. Fig. 6.—Spermatozoa of various amphibians. A. Desmognathus phoca. B. Bombina bombina (after Retzius). C. Hyla arborea (after Retzius). D. Crypto- branchus alleganiensis (after Smith). , cytoplasmic body. Hynobiidae and Crypto- branchidae, but all higher groups except the specialized Meantes possess a series of tubules in the roof of the female cloaca which retain, for varying periods, the sper- matozoa usually picked up en masse in the form of a sper- matophore (Fig. 7) by the female with her cloacal lips. These tubules known collec- tively as the " spermatheca " are homologous with a smaller or greater part of the pelvic gland of the male (Noble and Pope, 1929). It has been assumed that the eggs are fertilized as they pass by the spermatheca, but there is evidence that in Salamandra at least, the spermatozoa migrate up the oviduct before the time of egg laying (Weber, 1922). The spermatozoa make their way through the gelat- inous capsules of the egg, aided by the swimming move- ments of their tails and apparently also by the diges- tive action they exert on the capsules (Wintrebert, 1929). In the case of the primitive frog, Discoglossus, the sper- matozoa, although more than 2 mm. in length, are almost completely immobile (Hib- bard, 1928). Nevertheless, they are carried through a thickened portion of the egg. 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 Noble, Gladwyn Kingsley, 1894-1940. New York : McGraw-Hill
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