1910.] ORGANS OF THE FISH CHIMERA MOXSTROSA. 511 



which have attained sexual maturity. With the material at my 

 disposal I have been able to make additions to the above accounts 

 and also to verify much of the early work which some later 

 writers have in part disputed. 



My best thanks are due to Professor W. N. Parker of this 

 College, who suggested the work and rendered me much assistance 

 by his friendly criticism and advice in the course of these 

 investigations. A preliminary account of the relations of the 

 vasa efferentia has already appeared under our joint names (15). 



Historical. 



Leydig (1851) described the urogenital system of Chimcera 

 monstrosa, both male and female. He observed the network of 

 small ducts on the ventral surface of the testis and the manner 

 in which these minute ducts unite to form the larger ducts — vasa 

 eS'erentia — which are directed towards the " Nebenhoden " or 

 coiled anterior portion of the sperm-duct. The different regions 

 of the sperm-duct are described, though not by the aid of trans- 

 verse sections, but by dissection only. Moreover, Leydig's work 

 is very important in that he differentiates in the male the 

 posterior brown kidney from the anterior white structure called 

 by Hyrtl the " Leydig's gland," and he examined the secretion 

 from this latter. The author concluded that it must be regarded 

 as an accessory genital gland. In his account of the female 

 organs Leydig made special reference to the " shell gland " and 

 " uterus " of the oviduct, and looked upon the " digitiform 

 gland" — the "receptaculum seminis" of later writers — as most 

 probably an accessory female genital gland. 



Hyrtl (1853) continued Leydig's work on Chimcera, although he 

 was not so fortunate in obtaining fresh material. He could not 

 decide whether the cavity dorsal to the peritoneum between 

 testis and " Nebenhoden " was a lymph sinus, or whether it was 

 in connection with the anterior coiled end of the sperm-duct and 

 consequently a ccelomic intermediary between the testis and its 

 duct. Both Leydig and Hyrtl believed that vasa efferentia 

 must be present, but could not locate them with accuracy, nor 

 determine their relation with the sperm-duct. Hyrtl regarded 

 the most anterior duct from the Leydig's gland as the real 

 beginning of the sperm-duct : the " digitiform gland " was held 

 to be a reservoir for the reception of the sperms of the male. 



Mazza (1894) believes that the testis is not connected with its 

 " Nebenhoden," the spermatozoa from the former reaching it by 

 first passing into a portion of the body cavity and thence getting 

 into the coiled anterior end of the sperm-duct by means of canals 

 ('^ mesonephric tubules). 



Redeke (1898) does not throw any light on this point. He 

 divides the kidney into cranial, median, and caudal zones ; but 

 this distinction is untenable, since the cranial zone as indicated in 

 his figures is in reality the anterior coiled end of the sperm-duct, 



