Description of Some Japanese Polyclad Tarbellaria« 47 



Body elongate, anteriorly rounded, posteriorly bluntly pointed, trans- 

 lucent, of an olive-buffy colour. Tentacular eye-spots in a crowded cluster 

 at base of each tentacle ; cerebral eye-spots scattered over brain region on 



either side of the median line 5. N. hu mil is. p. 11. 



b* Nuchal tentacles absent. With penial stylet. 



Body as in the preceding, translucent, huffy, with a brownish orange 

 stripe in the median line. Tentacular and cerebral eye-spots blend together, 



distributed on either side of brain Q. N. delicata. p. 13. 



f} Witbout true seminal vesicle and accessory vesicle to vagina. 



Nuchal tentacles present. With large accessory seminal vesicle. Penis 

 with stylet Genus Hoploplana. 



Body broadly oval. Ground colour milky white or somewhat huffy, 

 traversed by broad radial bands of a russet or brownish russet colour, which 

 bands reticulate in the median or central parts, bringing about a limited 

 number of unpigmented and unequal sized mesh-like spaces. Tentacles 

 slenderly conical. Tentacular eye-spots forming a complet 3 circle ; cerebral 

 eye-spots in two groups closely inside the tentacular. . .l.H. ornata. p. 15 

 «J. 8 Prostate separated from ejaculatory duct and opening into it by a distinct 

 duct. 

 g. % Without penis. 



c. 4 Nuchal tentacles absent. Prostate ventral in position. With true 

 seminal vesicle. Cirrus cavity beset with chitinous bristles. Accessory 

 vesicle of vagina small and rudimentary Genus Neoplanocera. 



Boly elongate-oval, pale-yellowish coloured. Tentacular and cerebral 



eye-spots blend together, arranged on either side of median line ■ 



8. N. elowjata. p. 17. 



<J.* Nuchal tentacles present. Prostate dorsal in position. 

 a. 5 Without bursa copulatrix. 



With true seminal vesicle. Cirrus cavity beset with chitinous bristles. 

 With vagina bulbosa. Accessory vesicle of vagina small an 1 ru limentary . 

 Genus Planocera. 



a. 6 Boly broadly oval, large. Colour variable, more or less dark on 

 account of blackish punctate pigments present all over in reticular dis- 

 tribution, leaving numerous small mesh-spaces free of them. Tentacles 

 sometimes more than one in a group on each side. Tentacular eyespots in 

 close circular group ; cerebral eye-spots arranged over brain on either side of 

 the median line 9. P. reticulata, p. 19. 



b. 6 Body oval, comparatively small, of a dark purplish colour. 

 Tentacular group of eye-spots in close circle ; cerebral eye-spots in two 



paired groups 10. P. purpurea, p. 22. 



b. h With bursa copulatrix. 



