286 ASAJIRO OKA; ON SOME NEW 



Orohdella octonarici nov. sp. 



Diagnostic Gha meters. 



Body^ subcylindrical, more or less flattened toward the hind end ; 

 lateral margins parallel except near the extremities. 



Pdngs, 171. 



Somite, when unabbreviated, consisting of 8 rings. 



Mouth, occupying a space corresponding to the G foremost rings ; 

 7th and 8th rings forming, on the ventral side, the posterior lip of the 

 mouth. 



Ejies, in one pair, situated at the anterior margin of the second 

 ring, near the lateral borders of the anterior lip of the mouth. 



Genital on flees. The male orifice is on the 51st ring, the female 

 orifice on the 62nd ; 10 rings are between the rings bearing them. 



Glitelhiui embraces 24 rings, beginning with the 41st and ending 

 with the ()4th. 



Acetabulum, small, the diameter less than one-third the width of 

 the animal, in large specimens hardly of any suctory function. 



Anus, on the dorsal surface of the acetabulum, about a rings 

 breadth behind the posterior margin of the last ring. 



This species is represented in my collection by three specimens 

 only, whose dimensions are as follows : 



Lensfth, 270 mm. loO mm. 80 mm. 



Width, 14 nîm. 9 mm. 12 mm. 



Depth, 10 mm. 6 mm. 5 mm. 



In this species the rings show someti mes a tendency to be divided 

 into secondary rings by means of shallow grooves. Toward both 

 extremities, especially at the head end, we find also many rings that 

 are double on the dorsal surface but single on the ventral. In the 

 above diagnosis, such rings are counted as separate. The breadth of a 



