274 TRANSACTIONS LIVERPOOL BIOLOGICAL SOCIETY. 



Explanation of Plates. 

 Keference Letters. 



acg. anterior gland of cerebral 



organ. 

 be. buccal vascular commis- 

 sure. 

 cbv. commissural vessel 



between dv and Ibv. 

 ce. ciliated canal of cerebral 



organ. 

 erne, circular cephalic muscles. 

 c?nl. longitudinal cephalic 



muscles. 

 en. cephalic nerve. 

 corg. cerebral organ. 

 cugl. glandular cutis. 

 cvl. cephalic vascular loop. 

 dc. dorsal commissure of 



brain. 

 dg. dorsal ganglion. 

 dv. median dorsal blood 



vessel. 

 ep. epithelium. 

 exd. excretory duct. 

 ext. excretory tubules. 

 ft. frontal organ. 



gc. ganglion cells. 



gd. gonidial duct. 

 lis. head slit. 



id. intestinal diverticulum. 

 iep. intestinal epithelium. 

 Ibl. lateral blood lacuna. 

 Ibv. lateral blood vessel, 

 m. mouth. 



me. circular muscle layer. 



mcp. circular muscles of pro- 

 boscis. 



mcr. muscle cross. 



mdv. dorso- ventral muscles. 



mli. internal longitudinal 

 muscle layer. 



mlo. external ditto. 



mlp. longitudinal muscles of 

 proboscis. 



n. nerve to eye. 



nd. median dorsal nerve. 



nl. nervous layer. 



nip. nervous layer of pro- 

 boscis. 



nuc. nuclei. 



ocg. ganglion cell (?) layer of 

 eye. 



oes. oesophagus. 



oesc. oesophageal nerve com- 

 missure. 



oesl. oesophageal vascular 

 lacunae. 



oesn. oesophageal nerve. 



oep. oesophageal epithelium. 



ogl. gland cells round oeso- 

 phagus. 



ov. ovary \ 



p. proboscis. 



par. parenchymatous cells. 



peg. posterior gland of cere- 

 bral organ. 



