476 W. s. NICKERSON, 



amount of distortion should be found in Cunningham's drawings, it 

 would not indeed be surprising, since all of his figures were drawn 

 without the aid of a camera. An examination of my own drawings, 

 which were carefully made from camera outlines will, however, show, 

 I think, that the suckers are quite as distinct as Cunningham has 

 represented them. 



But there are yet other differences between Sticliocotyle and Macr- 

 aspis, which seem to me too great to be explained away by the 

 fact that Stichocotyle is a larval form. The acetabula of Macraspis 

 are so confluent as to make a single compound sucker extending along 

 nearly the whole ventral side of the body, whereas iu Stichocotyle a 

 similar connection of the suckers has been outgrown at an early stage 

 of their ontogenetic development, so that they are now quite distinct 

 and separated by considerable spaces (PI. 29, Fig. 7) ; furthermore in 

 Stichocotyle, they stop short of the posterior extremity of the body 

 (PI. 31, Fig. 22), whereas in Macraspis the ventral sucker extends 

 over the posterior end of the body and upon to the dorsal side. 



There also seems to be a somewhat greater relative distance be- 

 tween the anterior sucker of Stichocotyle and the oral extremity of the 

 worm than is shown in the figures of Macraspis between the anterior 

 end of the ventral sucker and the anterior end of the body. It is 

 perhaps not improbable that the adult of Stichocotyle may be found 

 nearly enough related to Macraspis elegans Ols. to be put into the 

 same genus with it, but I am convinced that this species is not the 

 larval form of the worm described by Olsson. 



Any conclusions which may be reached concerning the relations 

 of these two forms will, however, be only tentative until the anatomy 

 of Macraspis shall have been definitely made out and the adult form 

 of Stichocotyle discovered. It would seem , however, even from our 

 present knowledge, that Stichocotyle has quite as good claims to be 

 considered a genus of the family Aspidohothridae as has the imper- 

 fectly known Aspidocotyle Dies. It may therefore be provisionally 

 described as follows. 



Genus Stichocotyle Cunn., 1884. 

 Body elongated, cylindrical, tapering toward posterior end. Suckers 

 numerous (7 — 22) in a single row along mid-ventral side, distinct 

 from one another. Mouth terminal ; pharynx medium; intestine simple, 

 tubular, extending to very near posterior end of body. Genital orifice, 

 median, ventral, in front of anterior sucker. Testes two, in middle 



