Description of Some Japanese Polyclad. Turbellaria. 49 



]\Iale copulatory organs single or paired Genus Pseudoceros. 



a* Penis single. 



a. 5 Body somewhat oval, with strongly crenulated margin. Dorsal 

 surface showing all over a coarse reticulum of broad olive-gray bands, with 

 a number of much lighter coloured mesh-like spaces of various sizes. 

 Minute black, pigment dots scattered nearly uniformly all over the surface 



17. P. reticulata, p. 35. 



b. s Body oval, with frilled margin. Dorsal surface rosy colour with a 

 number of scattered blackish spots and a lightly coloured median stripe ; with 

 a blackish marginal and a russet brown submarginal band all around . 



18. P. laeteus ? p. 37. 



b* Penis paired. 



c. 5 Body oval, with somewhat wavy margin. Colour velvety black, 

 bordered all round by a russet brown marginal and a clear yellow sub- 

 marginal band 19. P. luteomarginatus. p. 37. 



d. 5 Body broadly elliptical, with frilled margin, of a brownish black 

 colour, margined completely around by a narrow but well-defined blackish 

 band and showing two light-coloured longitudinal bands in the median zone 



20. P. nigromarginatus. p. 39. 



b.- Marginal tentacles projecting, not fold-like ; pharynx cylindrical ; gut branches 

 not numerous. 



With or without minute dorsal papillse. Terminal branches of intestine 



opening externally by minute pores on lateral body margin 



Genus Cycloporus. 



Body oval, of an ochraceous colour, flecked with numerous russet and 



some darker spots 21. C. papillosus. p. 40. 



b. 1 Without marginal tentacles. Intestinal branches giving no evidence of forming 

 an anastomosing system. 



Pharynx cylindrical, anteriorly directed. Penis with stylet. Prostate 



paired Genus Prosthiostomim. 



c. Cerebral eye-spots in two linear .groups. 



Body elongate, of a buffy colour, nearly cinnamon in the median line 



22. P. siphunculus. p. 41. 



d? Cerebral eye-spots in two compact clusters. 

 c. z Marginal eye-spots few in number. 



c. 4 Body of an oblong shape, rounded at both ends, light buffy in ground 

 colour, uniformly dotted all over with numerous small spots of an ochraceous 



colour 23. P. grande, p. 42. 



d* Body elongate, yellowish buffy except at the head end, marked all over 



with irregular brownish blotches 24. P. marmoratum. p. 43. 



d.* Marginal eye-spots numerous. 



