686 



ZOOPHYTES. 



mal. These organs are somewhat warty, and, as shown by Corda, 

 the warts, which are arranged spirally around them, are furnished 

 with short bristles, and an exsertile dart, used, as is supposed, for 

 securing their prey. 



FAMILY II. SERTULARIDJS. 



Hydroidea gemmis persistentibus ; poly pis sessilibus ; ovulis pluribus 

 vesiculo indusis, lateralibus. 



Buds persistent; polyps sessile; ovules included in a vesicle, lateral. 



The species of this family are distinct from the Campanulariae, in 

 having the calicles without pedicels, and forming, to the naked eye, a 

 denticulate edging to the delicate branchlets. The latter also differ 

 in their modes of developement, in which respect they are near the 

 Tubularidas. 



The following are the characteristics of the genera : 



I. Polyps in one series, branches therefore secund. 



1. ANTENNULARIA. (Lamarck.) Not plumose. Calicles tubular or campannlate. 



2. PLUMCLARIA. (Lamarck.) Plumose, pinnate, or decompound pinnate. 



II. Polyps in two series. 

 a. Series uninterrupted. 



3. SERTULARIA. Calicks urceolate ; attached at base, with the summits more or less 

 free. This genus includes the Dynamene, of Lamouroux, which was instituted for spe- 

 cies having the cells opposite, instead of alternate. 



4. THUIARIA. (Fleming.) Calicles attached by one side as well as at base, not free 

 at apex. This genus is the Biseriaria, of Blainville, a name substituted by that author 

 for Fleming's. 



5. THOA. (Lamouroux.) Calicles very short tubular or campanula^. The habit of 

 the Those, as suggested by Milne Edwards, is much like that of the Campatnilarie, and 

 it may belong to the following Ihmily. 



l>. Polyps in successive groups, arising from a periodicity in budding. 



6. PASYTHEA. (Lamouroux.) 



