148 



Sex-Reversal in Frogs and Toads 



Left gonad. An ovo-testis with a larger six-lobed ovary-portion, 

 upon the inner border of which, at about its mid-point, was situated a 

 small spherical lobule of testicular substance. 



Vasa efiferentia entered into functional relationship with the sper- 

 matic and ovarian tissues of both gonads. 



Seminal vesicles small and fusiform. 



Miillerian ducts well-developed. 



On section, the ovarian patch upon the right gonad contained but a 

 single ovum, and the rest of this gonad was purely testicular. The tes- 

 ticular patch upon the left gonad had the structure of normal testis but 

 at one point it contained a well-developed ovum. 



Fig. 9. Fig. 10. 



10. Crew. (2.) R. temjporaria. Adult. Killed June. Secondary 

 sexual characters typically male. 



Right gonad. An ovo-testis having the appearance of a malformed 

 testis, irregular in outline and with its surfaces scored with deep grooves, 

 which bore along its outer border a broad band of dense black pigment, 

 which in some places was flatly applied to the surface of the testis and 

 in others was piled up into nodular prominences resembling ova. 



Left gonad. An ovo-testis consisting of three lobes, of which the 

 anterior and middle were testicular, but bore a band of dense black 

 pigment similar to that of the opposite gonad along the outer border, 

 while the posterior lobule was ovarian, the j)igraent of which was con- 

 tinuous with the band upon the outer border of the other two. 



Vasa efferentia present on both sides. 



