ACTIN0Z0A. 203 



thecse through their entire height. Each cor alii te 

 has its chambers slightly interrupted by a few 

 dissepiments. 



The members of another family, Astrceidce, are 

 either simple or composite, but there is no proper 

 ccenenchyma, as in the Ocidinidce. The epithecae 

 or coste form the chief substance of the mass by 

 which, sometimes, the corallites are separated. 

 Many Astrceidce present that rapid fissive develop- 

 ment of the corallum, whose curious results have 

 been already indicated in the case of Meandrina. 

 Dissepiments, in most, are numerous. In number 

 of genera and species, perhaps, also, of indi- 

 viduals, and, apparently, in general importance, 

 the Astrceidce seem, to surpass all other families of 

 the class Actinozoa. 



The Fungidce are at once distinguished from 

 the three families just noticed by the possession of 

 synapticulse. Dissepiments are absent, nor can 

 it be said in many cases that a proper theca exists ; 

 the septa passing, without interruption, into the 

 costee, save at the base of each corallite. Both 

 simple and composite Fungidce occur, the latter 

 multiplying by lateral gemmation. 



In the somewhat porous condition of their ill- 

 developed theca the Fungidce may be said to 

 differ from other Aporose Zoantharia, and ap- 

 proach the two next families, collectively distin- 

 guished by the title of Perforata. These, like 

 the Ajporosa, have a well-marked septal appa- 

 ratus, and present no traces of tabulse. 



^ Among the Madreporidce the sclerenchyma is 



simply porous, the septa are distinct, and but 

 very slightly perforate. Save in Fupsamnia and 

 some of its allies, the corallum is composite, but 



