G. EUNICEA. 217 



CORKY. 



5. Pl EX AURA snberosa. Dichotomous or branch- 

 ing ; branches long and diffuse ; cells radiated. 



Indian seas, and Africa. 



BENDING. 



6. Plexaura homomalla. Branches numerous, 

 dispersed, and often bowed down ; cells dispersed ; 

 rind brown or reddish ; height about three decime- 

 tres. 



American seas. 



OLIVE-COLOURED. 



7. Flexav R A olivacea. Very branching ; branches 

 scattered, and rather pinnated ; rind olive-colour ; 

 cells dispersed, and thinly sown ; size about one de- 

 cimetre. — Plate 16. 



East Indies. 



EUNICEA. 



A TREE-FORMED, branching Polypidom; axe al- 

 most always compressed, particularly at the juncture 

 of the branches ; covered with a thick cylindrical 

 rind, and strewn with projecting papillae, which are 

 always scattered and polypous. 



In this genus the polypi are always placed in pa- 

 pillous cells, often several millimetres in length and 

 breadth, sometimes rather smaller, and always re- 

 Cor, 2 E 



