On Three New Species of Hymeiwiepts 

 found in Japan. 



By 



S. Yoshida. 



Zoological Institute, Sci. Coll., Tokyo. 



With Plate VIL 



In my studies on avian Cestodes found in Japan, no less than 

 six species of Hymcnolepis have thus far been met with. Of these, 

 three are well represented by mature and well preserved specimens, 

 enabling me to study them in some detail. The three species, two from 

 the chicken and one from common teal, I consider to be new and 

 will be described in this paper. They are all remarkably small- bodied 

 species, — much smaller than most of the numerous known species of 

 the genus. 



I beg here to express my thanks to Professor Ijima for the many 

 useful advice given me during my work in the Zoological Institute. 



1. Hymeiiolepis exigua n. sp. 

 PI. VII, figs. i-io. 



The cestode species here described as new under the above name 

 occurs in abundance in the duodenal parts of the intestine of chickens 

 in Tokyo. The specimens were obtained chiefly on three occasions, 

 viz., Sept. 23, 1905; April 6, 1906; and April 27, 1908. They were 

 found either attached by the scolex or free in the chyme. 



Diagnosis. 



Length 2-7 mm. Rostellum with a single circle of 10 hooks at 

 apex. Head variable in shape, 0.17-O.21 mm. broad as well as long. 



