COLD-BLOODED VP^RTEBRATES 



10,^ 



hiyo develops in the follicle, which even- 

 tually ruptures at the site of the i)roi)yle and 

 releases the young fish for birth.-^ 



Some female fish are able to store sperm 

 in the oviduct or ovary for long periods, 

 making possible the fertilization of the eggs 

 months after contact with the male. Sperm 

 storage is reported for sharks and rays (Lo 

 Bianco, 1908-19091, and is common in the 

 Embiotocidae and Poeciliidae.-- 



Xothing is known regarding the endocrine 

 control of fertilization and sperm storage. 



Amphibians 



Salamander sperm are transported in 

 spermatophores (Noble, 1931). Spallanzani 

 knew in 1785 (Jordan, 1891) that several 

 European salamanders somehow practice in- 

 ternal fertilization, although he was not 

 aware that the female usually picks up with 

 her cloacal labia the spermatophores which 

 the male has just shed. Among the urodeles, 

 Cryptobranchoidea and ^iren are excep- 

 tional in that the males do not form sper- 

 matophores, the females lack spermathecae 

 (see below), and fertilization is external 

 (Dunn, 1923). 



Most female urodeles have special semi- 

 nal receptacles, or spermathecae, in which 

 the sperm are stored after the spermato- 

 phores disintegrate within the cloaca ( Dunn, 

 1923; Noble, 1931). The spermathecae are 

 actually cloacal glands, in the depths of 

 which the sperm congregate. As Noble points 

 out, de Beaumont ( 1928) proved the homol- 

 ogy of these glands with the cloacal glands 

 of the male. He transplanted testes into fe- 

 male Triton (Triturus) cristatus, and 6 to 

 10 months later found that the cloacal glands 

 liad assumed the secretory appearance char- 

 acteristic of the male. (It will be recalled 

 that the homologous male glands form the 

 spermatophores. I Noble (1931) has traced 

 the jihylogeny of the spermatheca. 



-^Wyman, 1854; Philippi, 1908; Scott, 1928; 

 Bailey, 1933; Purser, 1938; Eraser and Renton, 

 1940; Mendoza, 1940. 



-- Cymatogaster (Eigenmann, 1892a; Turner, 

 1938b), Amphigonopterus (Hubbs, 1921), Xipho- 

 phorus (Vallowe, 1953), Platypoecihis (Tavolga 

 and Rugh, 1947), Glaridichthys (Philippi, 1908; 

 Winge, 1937), Lebistes (Vaupel, 1929; Purser, 1937; 

 Clark and Aron.son, 1951), Gambusia (Dulzetto, 

 1928), and Heterandria (Eraser and Renton, 1940). 



Baylis (1939) kept a female *S. .sa/a/zia/^r/ra 

 in an acjuarium, isolated from all other sal- 

 amanders. In 2 weeks she produced a brood 

 of motile larvae, and did so again almost 2 

 years later. Baylis feels that it is usual for 

 the female to store sperms in her spermathe- 

 cae from impregnation in the summer at 

 least until after a brood is born the next 

 spring. The stored sperm then fertilize in- 

 ternally the next batch of eggs. The long 

 "gestation period" for this brood includes, 

 incidentally, several months of hibernation. 

 Adams (1940) found sperm in the sperma- 

 thecae of the newt, Triturus viridescens, 

 during every month of the year, but in 

 greatest quantity in the fall and spring. 



Reptiles 



Female reptiles may store sperm which re- 

 tain their fertilizing capacity for months or 

 even years, possibly an advantage in that 

 members of some species are slow moving 

 and relatively scanty, with conseciuent re- 

 duction in the opportunities for mating. Iso- 

 lated diamond back terrapins, Malaclemmys 

 centrata, have been known to lay fertile eggs 

 (as indicated by the presence of an embryo) 

 as long as 4 years after the last mating 

 (Barney, 1922; Hildebrand, 1929). A similar 

 record has been established by the box tur- 

 tle, Terrapene c. Carolina (Ewing, 1943). 



An instance of sperm storage in a chame- 

 leon, Microsaura p. pitmila has been re- 

 ported (Atsatt, 1953) 



Prolonged sperm storage has been ob- 

 served most frequently in female snakes, 

 some of which have been proven capable of 

 keejjing sperm alive and functional for up 

 to 5 years (see Fox's review, 1956, for all 

 reptiles) .^^ 



'^ Agkistrodon contortrix, 11 days (Gloyd, 1933) ; 

 Causus rhombeatus, 5 months (Woodward, 1933); 

 Crotnlus v. viriditi, throughout winter (Rahn, 1942; 

 Ludwig and Rahn, 1943); Vipera aspis, through- 

 out winter (Rollinat, 1946); Boiga multimaculata, 

 1 year (Kopstein, 1938); Coronella austriaca, 

 throughout winter (RoUinat, 1946); Drymarchon 

 cornis couperi, 4 years and 4 months (Carson, 

 1945); Lcimadophis viridis, delayed fertilization 

 (Mertens, 1940); Leptodeira albojusca, 1 year 

 (Kluth, 1936); L. annulata polysticta, 5 years 

 (Haines, 1940); Nntrix natrix, throughout winter 

 (Rollinat, 1946; Petter-Rousseaux, 1953); A^. sub- 

 miniata, 5 months (Kopstein, 1938); A'', vittata, 

 VA years (Kopstein, 1938); Storeria dekayi, 4 



