HERMAPHRODITISM IN EURYCEA BISLINEATA. 353 



All individuals 



Total number sexed 1113 



Number of males 574, or 51.57% 



Number of females 524, or 47.08% 



Number of hermaphrodites 15, or 1.35% 



The variation in the percentage of occurrence of hermaphrodites 

 in the different developmental stages has little significance be- 

 cause of the large probable error due to the small number of 

 specimens examined. It should be noted that the nearest approxi- 

 mation to the general average, 1.35 per cent., occurs in the case of 

 those stages in which there were the largest numbers examined. 

 The extremely low percentage in the adult group is noteworthy 

 and, though probably due to the small number of specimens used, 

 may conceivably indicate a lower degree of viability in the case of 

 hermaphrodites in adult life. The discrepancy in percentage of 

 males and females in the adult group may also indicate a dif- 

 ference in viability, but is more likely to be due to the fact that 

 the collections used were made mainly in the spring when the fe- 

 males would be more difficult to find because during the egg lay- 

 ing period they are under large rocks in the deeper water. 



The fact of real significance is that of the existence of hermaph- 

 roditism in every developmental stage, since together with the 

 approximate equality of the two sexes, it serves to eliminate any 

 claim that the condition in question is, in this species, merely a 

 transitory one. 



This establishment of a fairly constant percentage of occurrence 

 of hermaphroditism in Eurycca bislincata suggests the possibility 

 that a search for the phenomenon in other urodeles might reveal a 

 like frequency of occurrence. The urodeles offer an inviting field 

 for such investigation since so little has been done with them in 

 connection with the problem in contrast to the large amount of 

 attention which has been given to the anurans. 



DESCRIPTION OF REPRESENTATIVE CASES OF HERMAPHRODITISM 



IN Enrycea bislineata. 



Adult Stage. 



The one hermaphroditic adult found was an individual of 65 

 mm. in length which had the external characteristics of a female, 



