TRIBE II. CARYOPHYLLACEA. 357 



Quite simple, caliculato-ramose or aggregate. Corallum within trans- 

 versely septate, cells simply concave, regularly stellate ; no inter- 

 mediate dissepiments between the lamellae, and the sides of the 

 corallum, therefore, not cellular. 



The Calophylla pass gradually into the Cyathophylla, but still may 

 be readily distinguished by polishing down the exterior to a depth of 

 a line, when the edges of the vertical lamellae within are brought in 

 view, and the absence of intermediate dissepiments is apparent. The 

 lamellae of the cell sometimes appear split open or subdivided towards 

 the sides, and occasionally dissepiments may be distinguished between 

 the separated parts, when not apparent between the several lamellae 

 themselves. The septa, as may be seen in a vertical section, extend 

 quite across the interior. 



GENUS III. AMPLEXUS. SOWERBY. 



Cyathopkyllid<2 caulibus subcylindricis, kviter flexuosis. Corallum in- 

 terne transverso-septatum ; septis latissimis, fere rectis, usque ad latera 

 productis ; cellis multiradiatis, radiis interdum obsoktis. 



Cyathophyllida? with the stems subcylindrical, slightly uneven. Co- 

 rallum within transversely septate, septa very broad and nearly 

 straight, extending quite to the sides; cells many-rayed. 



The species of Amplexus are distinguished by their uneven cylin- 

 drical forms, having the internal septa extending quite across the whole 

 interior. They are thus closely related to the Calophylla, and it may 

 be a question whether the two genera should not be united in one, 

 unless it is thought best to pursue the system, apparently impracti- 

 cable, of forming separate groups of the cylindrical, columnar, and 

 missive species of the genus Cyathophyllum. 



The name Cyathophora has been applied by Michelin to fossil corals 

 near the above, but massive in structure, and the rays obsolescent. 

 They are often prismatic, like the Favosites, though larger. They 

 may be viewed as massive species either of Amplexus or Calophyllum. 



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