PLATE XV. 



FIG. 



1. BUGULA GRACILIS, var. UNCINATA; p. 86, nat. size. 



1 a. , a single cell, showing the position of the 



avicularium. 



2. - , zocecia, front view. 



3. , dorsal surface. 



4. , prehensile appendages. 



40. , primary cell and appendages. 



5. SCHIZOPORELLA vuLGARis, p. 244; showing the struc- 



ture of the cell. See Plate XXXVII. 



6. , var. with umbonate ovicell, and mucro on 



the front wall. 



7, 7 a. ESCHAROIDES QUINCUNCIALIS, p. 339 j fragment, 

 magnified and nat. size. 



7 b. - , young cell. 



7 c. , ooecium and orifice, forming together 



the " mamillary rising." 



