132 JESSE LE ROY CONEL 



(32 to 35 cm.)- Nansen thinks the change in sex occurs when 

 the animal reaches a body length of about 32 or 33 cm. Out of 

 hundreds of specimens examined by each of these investigators, 

 only a few males were found (Cunningham 8, Nansen 'very 

 few') and most of these were immature. Nansen regards the 

 males as merely transformed hermaphrodites and found all 

 transition stages between males and common hermaphrodites. 

 Cunningham found that in "nearly all specimens with very im- 

 mature eggs the posterior portion of the sexual organ had the 

 same structure as the testis," and that "in all specimens with 

 well-developed ovarian eggs .... with one exception, no 

 testicular portion was present in the sexual organs," then he 

 concluded "that in the young state the females are nearly, but 

 not quite always hermaphrodite, and that the testicular portion 

 normally disappears as the eggs become more mature." Nan- 

 sen states that ' ' on opening large specimens of Myxine, we gen- 

 •erally find well developed ova in their sexual organs. If we, 

 Jiowever, take smaller specimens, of about 28 to 32 cm. in length, 

 and examine their sexual organs, we generally find that the 

 anterior portion is but slightly prominent, and contains very 

 small and young ova, whilst the posterior portion is often very 

 broad and prominent, is lobate, and has a distinct whitish colour 

 along its margin, and has, in all respects, the appearance that 

 we would expect to find in a testis; and that it really is." He 

 concludes that "Myxine is generally, or always (?), in its young 

 state, a male; whilst at a more advanced age it becomes trans- 

 formed into a female. Indeed, I have not yet found a single 

 female that did not show traces of the early male stage." 



Schreiner found only 19 pure males out of 2500 specimens 

 examined, and they were seldom over 33 cm. long, the majority 

 of them being 30 to 31 cm. In a quite preponderating number 

 of individuals which were longer than 33 cm. there was a more 

 or less well-developed ovary and the testis part was sterile, and 

 in the males there was a more or less well-developed testis and 

 an abnormal or rudimentary ovary. In the females, the ovary 

 was well-developed and the testis part was usually rudimentary 

 or occasionally completely sterile. The testis was always ab- 



