Plate XV. 



1. Polyp of Alcyonium digitatum, enlarged, p. 195. 



2. Section tkrough polyp of A. digitatam (after Hert- 



wig), p. 191. 



3. Pennatula phosphorea (after Milnes-Marsliall), p. 



197. 



4. Virgularia mirabilis (after Milnes-Marsliall), p. 199. 



5. Gorgonia verrucosa (after Couch), p. 196. 



