'922.] 



A. Oka : Hirudinea from the Inle Lake. 



531 



1*5 mm. in width ; that from the first-named locality is 19 mm. 

 in length and 1/3 mm. in width. The hinder sucker is about as 

 wide as the body in both cases. 



External features. The mouth is very wide and occupies 

 the ventral surface of the first six rings. It is a spoon-shaped 

 hollow directly continuous with the oesophagus. No jaws nor 

 so-called pseudognaths are visible externally. 



The eyes, in two pairs, are situated on the fourth and 

 seventh rings, rather wide apart. In the individual from the first- 

 named locality the posterior pair presents an anomaly in the fact 

 that the right eye is placed one ring in front of the left eye, i.e. 



U 



CO. 



Text-fig. 5. — Jrocheta quadrioctilata, sp. nov. 

 a. Outline of entire animal : X3. 



Somites i-ix, dorsal view : 

 Somites i-ix ventral view 



X25. 

 X25. 



on ring 6. There is no marked difference in size between the 

 anterior and posterior pairs. 



The genital apertures are very small, almost invisible, except 

 the male opening of the smaller specimen which is rather pro- 

 minent. The male pore is situated close to the posterior bound- 

 ary of somite xi, the female pore just in front of the furrow 

 separating ring 6 and ring 7 of somite xii ; they are separated, 

 thus, by a space equivalent to four rings of a five-ringed somite. 

 The clitellum is not developed in either specimen. 



The colour is pale grayish, a little yellowish anteriorly. 

 There is no indication that the animal possessed any pattern 

 during life. The surface is perfectly smooth all over. 



As I have not studied the anatomy of the specimens, no 



