

Br 



MQ-- 



FiQ. 8. Chief forms of Polycladida : A-C, Acotylea ; D-F, Cotylea. A, Planocera 

 graffii Lang, nat. size ; B, Stylochoplana maculatn SUmps, x 7 ; C, Cestoplana 

 ruhrocincta Lang, x $ ; D, Anonymus virttis Lang, x 3, ventral surface ; E, 

 Thysanozoon brocchii Grube, nat. size ; the head is thrown back and the pharynx 

 (ph) is protruded. F, Prosthiostomum siphunculus Lang, x 3. Br, Brain ; CG, 

 cerebral eye group ; DM, true mouth ; Ey, marginal eyes ; m, mouth ; MO, 

 main-gut or stomach ; P, dorsal papillae ; Ph, pharynx ; *, sucker (ventral) ; 

 T, tentacles ; UP, dorsal median gut-branch. &, male, and ?, female, genital 

 aiKsrture, except iu D, where $ refers to the multiple penes. (After Lang and 

 Schmidt.) 



