156 • Sex- Reversal in Frogs mid Toads 



Miillerian ducts well-developed. 



On section, the right gonad contained one true ovum and many 

 doubtful ones. A lobe at the anterior pole of the gonad was regarded as 

 a rudimentary Bidder's organ. The true ovum lay within a seminal 

 tubule. The left gonad was also a testis but contained doubtful ova only. 



21. Pedaschenko. R. tcmporaria. Adult. Secondary sexual 

 characters typically male. 



Both gonads missing. 

 Mtillerian ducts well-developed. 



22. Marshall. (E.) It. temporaria. Adult. Secondary sexual 

 characters typically male. 



Both gonads missing. 

 Seminal vesicles present. 

 Miillerian ducts well-developed. 



23. Hooker. (A.) R. fusca. Adult. Secondary sexual characters 

 typically male. Killed April. 



Left testis missing. 



Seminal vesicles small. 



Mtillerian ducts weakly developed with narrow uterine segments. 



24. Marshall. (C.) R. temporaria. Adult. Secondary sexual 

 characters typically male. 



Right testis replaced by fat. 



Vasa efiferentia normal on the left ; absent on the right. 



Seminal vesicles present. 



Miillerian ducts well-developed. 



Sub-group 2. The testes were normal on inspection, 



25. Marshall. (A.) R. temporaria. Adult. Secondary sexual 

 characters typically male. 



Seminal vesicles were small. 

 Miillerian ducts well-developed. 



26. Gerhartz. R. esculenta. Adult. Secondary sexual characters 

 typically male. In addition to the usual male accessory sexual apparatus, 

 well-developed Mtillerian ducts were present. 



27. Tarnanl R. esculenta. Adult. Secondary sexual characters 

 typically male. 



Seminal vesicles were not present. 



Miillerian ducts were only moderately developed. 



28. TiCHOMiROW. R. esculenta. In an otherwise normal male 

 moderately well-developed Miillerian ducts were present. 



