32 Art. 2.— T. Kabuiaki : 



the late Professor Ijima in June, 1906, together with Poly, karafto 

 descrihed later on in the present paper. 



Form and Dimension. — In the living state the shape of the 

 body is very similar to that of the preceding. The frontal margin 

 is subtruncate and weakly crenate. The rounded auricular lobes 

 are scarcely prolonged into the tentacles, being anyway shorter 

 than in PI. vivida. Large specimens measured 10 mm. long by 

 1-5 mm. across in the broadest part. 



Colouration. — The translucent body is always colourless, with- 

 out any trace of pigment. The digestive tracts show themselves in 

 a milky white or somewhat yellowish or a dark colour. 



FJyes. — The two crescentic eyes are situated fairly distant 

 behind the frontal margin; the distance between them is shorter 

 than that of either eye from the lateral body-margin of the same 

 side. 



Digestive System. — The mouth-opening is situated at about 

 the hind end of the middle third of the body. The pharynx, 

 which is about one-fifth the entire length of the body, is inserted 

 at the middle of the body. The anterior main trunk of the intes- 

 tine gives ofï 10-11 pairs of lateral subdivided ^branches, wdiile the 

 posterior trunks are each provided with about 20 lateral branches. 



The genital organs unfortunately were not yet developed in 

 the specimens examined. 



tSorocelis siipporo Ij. et Kab. 



(PI. l.,fig. 12.— Text figs. 10, 11.) 



This species, which indicates some alliances with the forms 

 recorded from Lake Baikal and Tibet, is common in the clear 

 brook flowing through the grounds of Sapporo Agricultural College 

 in Hokkaido. Numerous specimens were collected b}^ the late 

 Professor Ijima in October, 1913. 



Form and Dimension. — The frontal margin is subtruncate and 

 gently arched in the median parts, which spread on each side into 

 the moderately distinct tentacles rounded at the end. The head 

 merges into the trunk, from which it is indistinctly separated by 



