58 THE ANTHOZOA 



sterile and fertile, gastrozooids and gonozooids. It is easy to trace the 

 steps which have led to the specialised Schizopathinae. Antipathes is a 

 nearly radial form, the reproductiv 7 e mesenteries but little longer than the 

 others, and the zooid is scarcely elongated in the transverse axis. In 

 Parantipathes the reproductive mesenteries are very long, the zooid is 

 much elongated in the transverse axis, and the two pairs of tentacles 

 belonging to the paragonadial chambers are shifted away from the 

 oral cone. The formation of incomplete septa dividing the para- 

 gonadial chambers from the remainder completes the Schizopathine 

 condition. 



FAMILY 2. LEIOPATHIDAE. Twelve mesenteries are present in the oral 

 cone. Genus Leiopathes, Gray. FAMILY 3. DENDROBRACHIIDAE. Axis 

 formed by several longitudinal lamellae arranged round a central rod ; 

 no central canal. Tentacles retractile, pinnate. Genus Dendrobrachia, 

 Brook. 



ORDER 3. Zoanthidea. 



Zoantharia paramera, mostly colonial, rarely solitary. Without a 

 skeleton, but often encrusted by sand. A sulcus is present, but no 

 sulculus. Mesenteries numerous, of two kinds, fertile macromesenteries 

 and sterile micromesenteries. The sulcar directives are macromesenteries ; 

 the asulcar directives are micromesenteries. In the remaining mesenteries 

 each macromesentery forms a couple with a microinesentery (one couple 

 excepted in Macrotypa), their well-developed retractor muscles being 

 vis a vis. After the first twelve mesenteries are established, new mesen- 

 teries are formed only in the sulco-lateral chambers. Mesogloea permeated 

 by ectodermic canals. 



FAMILY 1. ZOANTHIDAE. Division 1. Microtypa. The sixth primary 

 mesenteries are micromesenteries. Genera Zoanthus, Cuvier ; Mam- 

 milifera, Lesueur ; Corticifera, Lesueur. L)ivision 2. Macrotypa. The 

 sixth primary mesenteries are macromesenteries. Genera Epizoanthus, 

 Verrill ; Palythoa, Lam. 



FAMILY 2. SPHENOPIDAE. Solitary Zoantheae with rounded aboral 

 extremity. Genus Sphenopus, Steenstrup. 



ORDER 4. Edwardsiidea. 



Free solitary Zoantharia paramera with eight mesenteries and sixteen 

 to thirty-two tentacles. Body divided into capitulum, scapus, and physa. 

 Without a skeleton. Sulcus and sulculus present. Retractor muscles of 

 mesenteries well developed, placed on the asulcar aspect of the sulcar 

 directives, on the sulcar aspect of the remaining mesenteries. 



Genus Edwardsia, Quatrefages. 



ORDER 5. Proactiniae. 



Zoantharia paramera in which a variable number of mesenteries is 

 added to the eight Edwardsian mesenteries. The bilateral symmetry of 

 the Edwardsia form is retained. No skeleton. 



