HERMAPHRODITISM IN EURYCEA BISLINEATA. 357 



female elements are found in parts which are primarily male in 

 character. In fact no difference could be detected between the 

 ova among the testicular lobules and those of the more distinctly 

 ovarian part of the gonads except that the former had advanced 

 further in the matter of accumulation of layers of yolk. 



There was much mitotic activity in progress in the testicular 

 lobules, the same stage of mitosis being exhibited by all the cells 

 of a given cyst, a condition which is to be expected if one postu- 

 lates their formation by repeated divisions of a single primordial 

 spermatogonium. Thus the male elements, like the female, have 

 every appearance of undergoing perfectly normal development. In 

 the transition region from the testicular to the ovarian part of the 

 gonad. small testicular lobules appear which are somewhat degen- 

 erate in character. 



The posterior part of each gonad shows the typical ovarian 

 structure as demonstrated by the section of the left gonad in Fig. 

 , 4, with large central cavity surrounded by ova, each within its 



layer of follicle cells. 



The microscopic condition thus shown seems scarcely more ad- 

 vanced than that pictured and described by Chapin ('15) in the 

 gonads of her 46 mm. hermaphroditic " larva," which, in the ab- 

 sence of the more exact criteria of developmental stages of the 

 whole larval life such as we are here making use of, was designated 

 as a " larva " in the sense that it had not yet undergone trans- 

 formation. In reality it was probably an individual which was 

 approaching metamorphosis if not in actual metamorphic condi- 

 tion. In general this species shows much normal variation in the 

 developmental condition of the gonads at transformation and it 

 is thus not surprising that one individual previous to transforma- 

 tion should be in the same condition as another which has already 

 transformed. 



Our adult hermaphrodite is noteworthy, not only because it 

 shows that the condition is not merely a juvenile one, but also 

 because so far as external characters are concerned it appears to 

 be a female. These characters, it must be confessed, are not of a 

 very decided nature in this species, the presence of a spermatheca 

 being, indeed, the only unquestionable one. Moreover, the clo- 

 acal papillae which are the characteristic male structures, might 



