COLD-BLOODED VERTEBRATES 



1045 



sion of the nuptial pad (Kehl, 1944a) and in 

 male Xenopus by a much delayed drop in 

 serum calcium (Shapiro and Zwarenstein, 

 1933) . Removal of the testes is succeeded by 

 regression of sexual accessories in Bufo, but 

 removal of Bidder's organ does not have this 

 effect (Ponse, 1922a, b). Nuptial excres- 

 cences and other sex structures regress after 

 orchiectomy in Bombinator (Moszkowska, 

 1932) . In Rana, removal of the testes results 

 in diminution in size of seminal vesicles and 

 thumb pads and in failure of nuptial color- 

 ing and other sex characters to appear ( Aron, 

 1926; Christensen, 1931; Kinoshita, 1932), 

 but the linea masculina is not affected 

 (Davis and Law, 1935) . It is suggested that 

 once the latter is established it does not re- 

 quire hormonal support from the testis. 



In Triton {Tritunis) and Desmognathus, 

 two familiar genera of Salientia, orchiec- 

 tomy of adults results in regression or dis- 

 appearance of the dorsal crest, of the spe- 

 cialized epithelium of the Wolffian duct and 

 cloaca, and of male skin coloration. The 

 masculine premaxillary tooth is replaced by 

 a tooth like that seen in the female (Bresca, 

 1910; Aron, 1924b; Noble and Davis, 1928; 

 Noble and Pope, 1929). 



Reptiles 



Castration of the box turtle, Terrapene 

 Carolina, caused great reduction in the size 

 of the epididymis. Motile sperm could still 

 be obtained from the epididymis 74 days 

 after orchiectomy (Hansen, 1939). (The 

 ability of the surgically isolated epididymis 

 of the lizard to store sperm has already been 

 mentioned.) 



Sanfelice (1888) removed part of a testis 

 from one snake, Natrix {Tropidonotus) na- 

 trix, and one lizard, Lacerta agilis, and ob- 

 served some testicular regeneration. The lat- 

 ter phenomenon perhaps represents early 

 evidence of sorts for a gonadotrophic hor- 

 mone in these reptiles. In the blindworm, 

 Angitis fragilis, seasonal development of the 

 renal sexual segment and of other sexual ac- 

 cessories was prevented if the castration was 

 performed before the breeding season. If 

 done during this season, atrophy of the ac- 

 cessories followed in about 15 days (Herlant, 

 1933). Orchiectomy of Lacerta caused in- 



crease in the size of the fat bodies, disap- 

 pearance of the green body color, persistence 

 of the femoral glands in the quiescent phase, 

 involution of the epididymis, and absence 

 of epididymal and femoral gland secretion. 

 The sexual segment of the kidney remained 

 in the nonsecretory phase, and the epithe- 

 lium of the urogenital fossa was low and non- 

 glandular (Matthey, 1929; Regamey, 1935; 

 Padoa, 1929, 1933). Seasonal development 

 of sex accessories was prevented by castra- 

 tion of Takydromus (Takewaki and Fu- 

 kuda, 1935a). Sperm viability in the epidid- 

 ymis was much less than in normal lizards 

 (Takewaki and Fukuda, 1935b; c/. Hansen's 

 results, above, in the box turtle). Involution 

 of sexual accessories after orchiectomy also 

 occurred in Eumeces (Reynolds, 1943) and 

 Uromastix (Kehl, 1935, 1944b). 



Removal of the testes had no effect on the 

 renal sexual segment in the snake Tham- 

 nophis r. radix (Waters, 1940) but did in 

 Natrix (Takewaki and Hatta, 1941). 



IX. Effects of Androgens 



Sex hormones have been given experimen- 

 tally in a variety of ways. These hormones 

 are freely soluble in certain vegetable fats 

 such as sesame oil and in alcohols and are 

 slightly soluble in water. Solutions can be in- 

 jected subcutaneously, intramuscularly, or 

 intraperitoneally. Solid pellets made by 

 compressing the crystalline hormone can be 

 imi:)lanted in various body sites for slow, 

 continuous absorption. Sex hormones can 

 even be fed. Solutions can be applied to the 

 skin; in fish and amphibians, percutaneous 

 absorption can be achieved if the hormone is 

 dissolved in the aquarium water. Finally, in 

 one of the oldest techniques, testes or ovaries 

 can be grafted into experimental animals. 



Fish 



Administration of testicular hormone to 

 intact carp and of testosterone propionate 

 to hypophysectomized killifish accelerated 

 the rate of spermatogenesis (Castelnuovo, 

 1937; Burger, 1942). Intraperitoneal injec- 

 tion of androgens in Fundulus heteroclitus 

 stimulated increase in weight of the testis 

 even after hypophysectomy (Pickford and 

 Atz, 1957). Prcgneninolone (ethinyl testes- 



