GFLETETID^. 

 Ch^ETETIDtE. 



341 



This family includes only the single genus Chcetetes, all the known 

 species of which are found in the Carboniferous rocks, though vari- 



Fig. 221. — a, Fragment of a large corallum of Tetradiu7>i minus, Safford, from the Cincinnati 

 Group of North America, of the natural size ; b, Transverse section of the same, enlarged ten 

 times, showing the petaloid form of the tubes and the short septa ; c, Vertical section of the same, 

 similarly enlarged, showing the tabulae. (Original.) 



ous Monticuliporoids have been formerly referred to the same genus. 

 The type-species is the C. radians of the Carboniferous Limestone 



j^r 



p *V*C 



\ 1 If 



! ! : 



K J ■ • Z 



h 1 f yi 1 



A 



B 



Fig. 222. — a, Tangential section of CJuptetes Etheridgii, from the Carboniferous Limestone of 

 Westmorland, enlarged about ten times; B, Longitudinal section of the same, similarly enlarged. 

 a, Imperfect longitudinal partition produced by uncompleted fission of an old corallite. (Original.) 



of Russia, but the characters of all the known species are essentially 



in Chcetetes is massive or laminar, often 



the same. The corallum 



