134 



and through the formation of coarse cysts. Xo true tabulae 

 ai»' known; the polypites in some of the species apparently 

 remained connected throughout the life of the colony, 

 while in others the cavities of the corallites are separated 

 by a spicular partition. Surface formed by a wrinkled 



epitheca. 



Ceratopora jacksoni. Grabau. (Fig. 17.) (1899: Proc. 

 Boston So.-. Nat. History, Vol. XXVIII, p. 415, Pis. I.. II.) 



Distinguishing Characters.— 'Erect, irregular, and fre- 

 quently-branching corallum; cylindrical or trumpet-shaped 

 corallites: coarsely wrinkled epitheca with costal ridges; 

 coarse, irregular internal cysts, arranged semi-concentric- 

 ally, with frequent projecting spine-like processes. 



3 /7. 



Fig. 18. Ceratopora dichotoma. (.a-d Specimens viewed from different positions, show- 

 ing the flattened under side, tin- calyx, cannation, ami lines of growth, x 3; (e> specimen 

 seeD from below, showing t li. - characteristic mode of branching— natural size: </) longi- 

 tudinal section of the procumbent portion of a corallite. showing the living chamber and 

 the cysts, x 5. (g) transverse section of procumbent tube, showing central cavity, cysts, 

 and hollow carina, x 7. (( Original.) 



