16 POLYZOA. 



FAMILY VI. MEMBKANIPOEAD^E. 



Membranipora (Joknst.). Cells open in front, 

 with raised margins ; usually encrusting sea-weeds, 

 more rarely shells and stones. 



M. membranacea. M. Flemingii. 

 pilosa. Fig. 25 ; n. s. and mag. Rosselii. 



coriacea. Lacroixii. 



lineata. monostachys. 



25 26 



Lepralia (Johnst.). Cells closed in front, spread- 

 ing from the centre outwards. 



JST.B. The British species of this genus, which 

 are very numerous, are thus subdivided by Mr. 

 Busk : 



* Furnished with birds'-heads. 

 a. Bird's-head medial and single, 



a. Above the mouth. 



L. Brongniartii. 



b. Below the mouth. 



L. Landsborovii. L. concinna. 



reticulata. verrucosa. 



auriculata. violacea. 



/3. Birds'-heads double ; or if single, on one side. 

 L. spinifera. L. coccinea. 



trispinosa. linearis. 



