CHAP. I 



CLASSIFICATION OF POLYCLADIDA 



19 



Classification of Polycladida. 



ACOTYLEA. 



Family. 



Planoceridae. 

 With dorsal tentacle 

 Mouth sub-central. 



Leptoplanidae. 

 "Without dorsal 

 cles. Penis 

 backwards. 



tenta 

 direc 



Genus. British Representatives. 



Planocera (Fig. 8, A). 



Imagine, 1 Planocera folium Grube. 



Conoceros. Berwick-on-Tweed. 



- Stylochus. - 'Stylochoplana maculata 

 Stylochoplana (Fig. 8, B). Quatref. Among brown 



Diplonchus. I weeds in Laminarian zone. 

 Planctoplana. 



( Lcptoplana tremellaris 0. F. 



Miill. 

 I L.fallax Quatref. Plymouth. 



c Discocelis. 

 Cryptocelis. 

 , i* - Leptoplana. . 



Trigonoporus. 

 I ? Polypostia (see p. 



L. drocbachcnsis Oe. Ply- 

 mouth Sound. 



L. atomata 0. F. Miill. 

 Doubtful species. 



Cestoplanidae 

 No tentacles. 



( Cestoplana (Fi 

 Body! 

 elongated. Penis | 

 directed forwards. v 



C). 

 In Mediterranean and 

 on French side of the 

 Channel. 



Enantiidae. r 



No sucker No tentacles. Enantia , 

 Main-gut very short. I ^.^ gea> 

 External apertures as 

 in Euryleptidae. v. 



COTYLEA. 



Anonymidae. ( 



Mouth central. No) Anonymus (Fig. 8, D). 



tentacles. With two| Naples (two specimens), 

 rows of penes. ' s 



1 55S^^ E) - 



Mdiginal tentacles J Psmdoceros ^ 

 folded. Mouth in y ^ 

 anterior halt. I 



Euryleptidae. 

 Tentacles usually pre- 

 sent and pointed, or 

 represented by two 

 groups of eyes. Mouth 

 close to anterior end. 

 Pharynx cylindrical. 



Prosthiostomatidae. 

 Tentacles absent. Body 

 elongated. Pharynx 

 long, cylindrical. 

 Penis with accessory 

 muscular vesicles. 



Prosthcceraeus. 



Cycloporus'. 



Eurylepta. 

 1 Oligocladus. 



Stylostomum. 

 \ Acer os. 



Prosthiostomum (Fig. 



F). 



Prosthcceraeus vittatus Mont. 



On west coast. 

 P. argus Quatref. Guernsey. 

 Cycloporus papillosus Lang. 



On Ascidians in 2-30 fms. 

 Eurylepta cornuta 0. F. Miill. 



On sponges and shells, 



2-10 fms. 

 Oligocladus sanguinolentus 



Quatref. 

 0. auritus Clap. Doubtful. 

 Stylostomum variabile Lang. 



