diief Generic Types of Palteozuic Corals. 



71 



ami intermediate areas of the coralliim is essentially and 

 I'lmdaint'Mtaily identieal. TIk'v difl'er, however, in \\\o struc- 

 ture ol' the yreat mass of endtjthecal tissue whieh occupies the 

 centre of the visceral chamber ; and these ditierences are shown 

 in the annexed sketches, where the stiiicture of the central area 

 of these forms is represented. 





IHagrams showing: the PtiMirluro of ClisiophjiUum and its nllie*. A. Dihu- 

 ni>ph}jUum ; W, A.-<jn'f/>ip/ii///i/ii> ; (J. liltixlophiiUiim : I >, type internn'- 

 diate between AsiiHlophylluin and lihufhtphiillum ; E, Clisiopfi>/l/iitu ; 

 F, ('ijrliiphijlhitn ; (i. transition-form between Koulnchopltiilbnu and 

 the typiral Clisiopliylloids ; II, Cdninophiillum (fren. nov. ) ; I, tran- 

 sition-form, near (t. Fi;f. K represents across section of C/iAinji/ij/ffinn 

 cnnifK^tiim, Keys., of the natural size, in which the external and in- 

 termediate areas are introdured as well as the central. Figs. A,T?, 

 C, D, and F are enlarjjfed, and represent only the central area of the 

 corallum ; to complete these figures, an external and intenriedidte 

 zone must lie added, a.s in tig. F,. Figs, d, 11, and I are likewi.se en- 

 larged, and represent the central aien of tlie corallum, along with the 

 inner ends of the septa. The letter /"indicates thep(j.Hiti()nof thefos-sula. 



