I. IJIMA AND T. KAIiURAKI. 



and slightly anteriorly directed. Body slender, superiorly convex, inferior- 

 ly flat, in the creeping state with lateral margins running nearly parallel for 



22 



21 



21. Polycehs aitriadata, n. sp. in the cleeping 

 state, about 4 X . 



22. Same. Diagram of sexual organs. 

 Index letters as in woodcuts 2, 4 and 8. 



the most part ; posterior body- 

 end rather rounded than obtusely 

 pointed. 



Exceptionally large speci- 

 mens in the fully extended state 

 reach 25 mm. in length and about 

 3^ mm. in breadth ; commonly 

 smaller, ic-15 mm. long by i-i£ 

 mm. broad in the creeping state ; 

 breadth and length in the ratio 

 of I : 7-10. 



Color of dorsal surface gener- 

 ally sepia-brown, the guts indis- 

 tinctly showing themselves in a 

 dark brownish color or in a 

 variety of other colors incidental 

 to gut contents. Ventral surface 

 of a pale color. 



Eyes extremely small, nu- 

 merous, numbering 3C-73 on 

 cither side, distributed in a 



horseshoe-shaped tract close to head margin, there existing in the width of 

 that tract commonly more than one eyes and only occasionally a single 

 eye. The tract may extend posteriorly for a length equal to about one- 

 eighth or one-sixth the entire body-length. 



Mouth situated at about the hind end of the middle third of body. 

 Pharynx inserted at about the middle of body-length. Anterior gut trunk 

 giving off 6-9 pairs of branches ; each posterior trunk with usually ic-17 

 lateral branches, those inwardly directed being either very small or, as is 

 frequently the case, joining together the two trunks. 



