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CHAPTER XIII. 



GENERA OF CH.ETETID.E AND MONTICULIPORID^. 



CH^TETID.^. 



Gcmis CiL-ETETES, Fischcr, 1837., 

 (Oryct. de Gouv. de Moscou, p. 159.) 



Gcii. Char. — Corallum massive, composed of long irregu- 

 larly prismatic erect corallites, which are closely contiguous, and 

 are completely amalgamated by means of their walls. Coral- 

 lites of one kind only, opening upon the surface by means of 

 irregularly polygonal, non-oblique calices, and destitute of true 

 septa. Walls imperforate. Tabulae complete, comparatively 

 remote, often placed at corresponding levels in contiguous 

 tubes. Visceral chamber often partially divided by an imper- 

 fect longitudinal septum (or by two such septa) resulting from 

 the uncompleted fission of the tube into two young corallites. 



Obs. — It is not necessary to enter here into a detailed ac- 

 count of the genus Chcetetes, except in so far as concerns its 

 relations with the genera Stciiopora, Lonsd., 2,Vi.^ Montiatlipora, 

 D'Orb., and even on this point little need be said. The type 

 of the genus CJicutctcs is unquestionably the great C. radians, 

 Fischer, of the Carboniferous Limestone of Russia, and the 

 characters of the genus must, therefore, necessarily be based 

 upon this species. This form was for the first time adequately 



