76 JESSE LE ROY CONEL 



The former investigated Bdellostoma forsteri, the latter Bdello- 

 stoma stouti. Both of these descriptions are confined almost en- 

 tirely to the structm-e and probable function of the pronephros, 

 and are comparatively incomplete. Scarcely anything is said 

 about the mesonephros. Price ('96 a, '96 b, '97, '10) has, how- 

 ever, given a detailed account of the development of the excre- 

 tory system in Bdellostoma stouti, which throws much light 

 upon the adult condition. Semon ('96) devotes one paragraph 

 to a comparison between the pronephroi of Mjrxine glutinosa and 

 Bdellostoma bischofi. 



After J. Mliller, Thompson ('59) and Streenstrup ('63) were 

 the next writers upon the generative organs of the Myxinoids, 

 each giving a short account of the mature ova of the European 

 Myxine. W. MiiUer ('75) contributed many points regarding 

 oogenesis in Myxine and gave the first description of the minute 

 structure of the testis. In 1886 Cunningham added a few more 

 points regarding the reproductive elements of Bdellostoma for- 

 steri and in 1887 he published the first detailed description of 

 the sexual organs and products of Myxine glutinosa, introducing 

 the subject of protandric hermaphroditism. Nansen ('87) sup- 

 plemented Cunningham's description with the results of further 

 investigations, which led him to agree with Cunningham that 

 Myxine glutinosa is a protandric hermaphrodite. Cunningham 

 ('92) next contributed a rather lengthly discussion of spermato- 

 genesis in Myxine. Ayers ('93) published the fii'st description of 

 the reproductive system of Bdellostoma stouti, and soon after 

 Dean ('99) gave an account of the structure of the eggs and 

 development of the embryo. The latest articles which have ap- 

 peared regarding this subject are those by A. and K. E. Schreiner 

 ('04, '05, '08) which consist of a description of the generative ele- 

 ments of Myxine glutinosa and a very thorough discussion of 

 spermatogenesis in Myxine glutinosa and Bdellostoma burgeri. 

 Besides the foregoing investigators, there are several who have 

 made minor contributions to our knowledge of the genital appara- 

 tus in Myxinoids. 



The literature contains only a very meagre description of the 

 mesonephros and the reproductive elements of Bdellostoma and 



