588 ZOOPHYTES. 



This family may be subdivided as follows : 



SUBFAMILY I. PENNATULIN^E. Polyps retractile. 



G. 1. Rcnilla. Free, explanate, unifacial (reniform). 



2. Veretillum. Very stout, oblong cylindrical, simple, with scattered polyps. 



3. Virgularia. Slender virgate, with very short pinnules or none. 



4. Pennatula. Pinnate and stout, or plumiform, with long pinnules. 



SUBFAMILY II. PAVONARINX. Polyps not retractile. 



5. Pavonaria. Virgate, polyps secund. 



6. Umbellularia. Virgate, polyps in a terminal cluster. 



SUBFAMILY I. PENNATULIN^. 

 Polypis retractilibus. 

 Polyps retractile. 



GENUS I. RENILLA. 



Liberce, explanata, unifrontes ; polypis sparsis retractilibus. 

 Free, explanate, unifacial; polyps scattered, retractile. 



1. RENILLA AMERICANA. (Ellis.) 



R. reniformis, margine acuto ; postice caudata, cauda subtus longitudi- 

 naliter sulcata. 



Reniforrn, margin acute ; behind caudate, with the caudal appendage, 

 below, longitudinally sulcate. 



West Indies. Off Rio Janeiro. Exp. Exp. 



Resembles a thick reniform leaf, with a stout pedicel. In the con- 



