EXPLANATION OF PLATE XXXIV. 



Figure 257. — Alcyonidium ramosum, (p. 708;) a young unbranched specimen, enlarged 

 two diameters. 



258. — Bugula turrita, (p. 712 ;) extremity of a branch, enlarged. 



259. — The same ; a branchlet more highly magnified. 



259a. — The same ; a branchlet bearing ovicells. 



260. — Crisia eburnea, (p. 707 j) a cluster of branches, enlarged. 



261. — The same; a branch bearing an ovicell, more highly magnified. 



262. — Membranipora pilosa, (p. 712;) a few of the cells, seen from above, mag- 

 nified. 



362a. — The same ; a single cell, seen in profile. 



263. — The same ; one of the zooids expanded. 



264. — Mollia hyalina, (p. 713 ;) one of the zooids in expansion, highly magni- 

 fied. 



(Figures 257, 259, 259a were drawn by A. E. Yerrill ; the rest were furiiislied by A. Hyatt.) 



