70 Bashford Dean tAemorial Volume 



Evidently the reproduction of these eels later became a subject of lively interest, for 

 in 1862 the Academy of Sciences of Copenhagen offered a prise for the discovery of the 

 manner of reproduction and development of Myxme glutinosa. Though many investiga' 

 tors have tried, no one has ever been able to solve this problem in the case of Myxine. 

 Dean, however, as has been stated above, succeeded in collecting the embryos of Bdellos' 

 toma stouti in sufficient numbers to work out the general development of this myxinoid. 



HERMAPHRODITISM IN MrXl?iE GLVTINPSA 



After J. Miiller (1843), Steenstrup (1863) of Denmark wrote the next paper pertaining 

 to the genital system of Myxine glutinosa. He described eggs of various si2;es in the ovary, 

 as well as a naturally deposited egg of Myxine which he found in a museum at Copen' 

 hagen. The label in the jar. stated that the egg had been recovered from the stomach of a 

 cod. In the one text-figure he illustrated the filaments, with their anchor-shaped hooks, 

 at each end of the egg, and also represented the operculum in one egg. 



W. Miiller (1875) was the next writer upon this subject. He was of the opinion 

 that ""Myxine ist gleich Amphioxus getrennten Geschlects," and described the testis, 

 as well as the ovary, as extending along the gut on the right side only, attached by a 

 mesorchium and mesovarium, respectively, to the mesentery. The ovary could be 

 identified by the eggs, the youngest of which were round, and the older ones ellipsoidal. 

 He doubted if J. Muller really saw the testis. He found the males occurring much more 

 rarely than the females, and "somewhat smaller in si2,e. According to him the testis 

 has the same position as the ovary, and can be recognised as such at the first glance, form- 

 ing a flat, gray, lobed mass along the free border of the mesorchium, and consisting of 

 a large number of follicles. Muller found no spermatozoa in the testicular follicles. His 

 figures, while not detailed, indicate that he undoubtedly saw the testis. 



J. T. Cunningham, of Edinburgh, published (1886.1) the results of his extensive 

 observations made upon numerous specimens of M^xnie glutinosa which had been caught 

 for him in the Firth of Forth. As one result of his investigations Cunningham con- 

 cluded that Myxine is a protandric hermaphrodite. He thought that Myxine glutinosa 

 while young is an immature male, then later becomes a mature male with small eggs in the 

 anterior part of the sexual organ, i.e., a functional male hermaphrodite, and finally that the 

 testis atrophies, the eggs become larger and the animal then is a female. The change from 

 a mature male hermaphrodite to the female was thought to occur when the eel reached a 

 body length of 32 or 33 centimeters. Cunningham (1886.2, p. 71) stated that in "nearly all 

 specimens with very immature eggs the posterior portion of the sexual organ had the same 

 structure as the testis," and that (p. 73) "in all specimens with well developed ovarian 

 eggs . . . with one exception, no testicular portion was present in the sexual organs." 

 Therefore, he decided that in the young state the females are nearly, but not quite always 

 hermaphrodites, and that the testicular portion normally disappears as the eggs become 

 more mature. It seemed to him probable that fertilisation is normally effected by herma- 

 phrodites, since true males are so rare. 



