HERMAPHRODITISM IN EURYCEA BISLINEATA. 361 



others with iron haematoxylin, and still others with safranin and 

 light green. The lobules of the normal testis (Fig. 6 A} are made 

 up of spermatogonia surrounded singly or in small groups with 

 follicle cells, with which the cysts later to be formed by the divi- 

 sion of these spermatogonia will be covered. Typical spermato- 

 gonial mitoses are seen in this and in other sections. In the her- 

 maphroditic gonads (Figs. 6 B and C) we find a testicular struc- 

 tufe corresponding in general to that shown by the normal testis, 

 with typical mitoses in evidence. At the level shown in C in which 

 the ovum constitutes practically half of the total diameter of the 

 gonad, the testicular part is not quite so far advanced as in B, but 

 is, in fact, in much the same condition as the more anterior region 

 of the normal testis. The ova shown in both of these sections are 

 typical, as will be seen by comparison with the section of the 

 normal ovary (Fig. 6 D), although they are not equal in size to 

 the larger ones of the normal ovary. 



Incipient Premetanwrphic Stage. 



In the examination of younger stages in which little or no tes- 

 ticular pigment had developed, reliance for the diagnosis of the 

 sex had to be based upon the shape of the ovary with its protrud- 

 ing ova to distinguish that organ from the slender testis or from 

 the testis with- female elements present in it. 



Figure 7 B shows the general appearance of the hermaphroditic 

 gonad of a 36 mm. incipient premetamorphic individual, and Figs. 

 7 A and C show gonads of a typical male and female of about the 

 same size and developmental condition. The smaller size of the 

 hermaphroditic gonad is again evidenced. The ova are of about 

 the size of the smallest seen in the normal ovary. 



The anterior part of the reproductive organs in each case was 

 sectioned transversely for the purpose of studying the relation of 

 the ducts ; while the posterior part, including, in fact, the major 

 part of the gonads themselves, was sectioned horizontally. Dela- 

 field hsematoxylin and iron haematoxylin staining were used. 



Histologically the developmental condition of these gonads as 

 shown in Fig. 8 A, B, and C is not essentially different from that 

 of the metamorphic stage, except that both in the normal testis 

 and in the testicular region of the hermaphroditic gonad there are 



