1922.] A. Oka : Himdinea from the Inlc Lake. 523 



nearly 3 mm. in width, the posterior sucker is about 1*5 mm. 

 across. 



External features. There is a single pair of eyes on the 

 second annulus. They are pretty large and distinct, and are 

 placed close together, almost touching with the base at the median 

 plane of the animal. The opening of the pigment-cup is directed 

 obliquely forward and toward the side. 



The oral sucker occupies the ventral surface of the first six 

 annuli, the ventral portion of annulus 6, which is very narrow on 

 that side, forming the posterior boundary of the sucker. The 

 mouth-opening is situated in the anterior half of the sucker just 

 below the eyes, corresponding in position with annulus 2. 



The genital apertures are separated by two rings ; the male 

 opening lies between annuli 26 and 27, the female opening between 

 28 and 29, counting each of those annuli at the anterior end, 



as. 



Text-fig. I. — Glossiphonia inleatia, sp. nov. 



a. Outline of entire animal : X3. 



b. Somites i-ix, dorsal view: X30. 

 r. Somites i-ix, ventral view : X 30. 



which are double in larger specimens, as two. Both pores are 

 small and inconspicuous. In most of the specimens the clitellum 

 was not distinguishable from the rest of the body. 



The anus is a small transverse slit placed behind the last 

 annulus. There is. however, a small ring-like portion of the body 

 on the dorsal surface of the sucker just behind the anus. 



The hinder sucker is directed ventrally and is attached to 

 the body by the ventral surface of the last three or four annuli. 



The specimens preserved in alcohol are of a uniform pale 

 grey colour, but there are indications that the animal was orna- 

 mented during life with roundish spots regularly arranged on the 

 dorsal surface, much in the same way as those of Hemiclepsis 

 marginata (2). In many individuals the crop with its paired 

 diverticula is recognizable externally on account of the dark 

 brown mass (coagulated blood of the host) it contains. 



Internal anatomy. The small mouth-opening leads into the 



