234 ASAJIRO OKA; ON SOME NEW 



these twenty-one ganglia, fifteen at least are situated at an interval of 

 four rings from each other. This regular arrangement of the ganglia, 

 taken together with the fact that the nephridial pores open on every 

 fourth ring, admits of no douht that in this species an unabbreviated 

 somite consists of four rings, although tliis number has never been 

 recorded for any leech, whether a Rhynchobdellid or a Grnathobdellid. 

 The sections show also that the ring, on winch the nephridial pores 

 open, immediately precedes the one containing the ganglion. This 

 leads us to the conclusion th;it, in this leech also, the ganghon lies in 

 the first ring, and the nephridial pores open on the last of each somite, 

 as is actually tlie case in every other Gnathobdellid. 



The specimens of this species were collected at Kinkwazan near 

 Gifu (Nawa), at Chi-on-in in Kioto (M. Kikuchi) and at Kibözan near 

 Kumamoto (Nakagawa). 



Orohdella Ijimaï nov. sp. 



Diagnostic ch aracters. 



Body subcylindrical, slightly tapering toward both ends. 



Riiigs 129 ; a few of the last rings again divided by furrows. 



Somite, when unabbrevifited, consisting of 6 rings. 



Month, occupying a sjjace corresponding to the 5 foremost rings ; 

 6th and 7th rings forming on the ventral side the posterior lip of the 

 mouth. 



Eyes, in one pair, at the anterior margin of the second ring. 



Genital orifices. The male orifice is situated on tlie o9th ring, 

 the female orifice on the 47th ; 7 rings between those bearing the 

 genital pores. 



Glitcllum embracin"- 19 rinofs, beoinninof with tlie 31st and ending- 

 with the 49th. 



