274 s. GOTO. 



three chitinous pieces, one somewhat large, saddle-shaped piece 

 in the middle, and two smaller pieces at the two ends (fig. 14). 

 There are two pairs of hooks at the posterior end of the body, 

 between the hindmost pair of suckers. The external pair 

 are considerably larger, and the hook is provided with a lateral 

 barb-like process at the middle ; they measure 0.128 mm. in 

 lenojth (fig. 15 b). The internal hooks are very slender and are 

 slightly curved at the middle ; they are only 0.048 mm. long. 



The common genital aperture is situated near the end of the 

 anterior slender portion of the body, and the vaginal opening 

 at a short distance behind it, at the boundary between the an- 

 terior two portions of the body. The vaginal opening is armed 

 with two chitinous bodies forming a pair, bearing numerous denti- 

 culi on the inner side. In their paper of 1889 Parona and 

 Perugia mistook the vaginal opening for the common genital 

 aperture, and although I have not access to their paper of 

 1892, it appears from the resume of Saint-Pemy, that they 

 repeat the same error in tlieu* note on Hexacolyle thynni [Saint- 

 Pemy, '98, p. 556], and mistake the common genital pore for 

 the vaginal opening. 



The ovary could fairly be made out in Dr. Stiles' s[)ecimen, 

 and is a triangular mass situated in the median line, at the hind 

 end of the second expanded portion of the body. 



Odocotyle scombri (Kuhn). 



In my " Studies " ['94, p. 206] I expressed the suspicion 

 that the two species described by me as 0. major and 0. minor 

 might have been confounded and regarded as a single species 

 by European writers. Pelying, however, on the figures of 

 Parona and Perugia ['89] I then concluded that my suspicion 



