100 A. E. Verrill — Bernmdlan and West Indian Reef Corals. 



become more solid and heavy than usual in that genus, but not more 

 so than in 0. hirtella and some other species. In both this and 

 hyades the septa of the third cycle are well developed and bend 

 toward and join those of the second cycles ; in both the septa are 

 thin and but little prominent above the wall; and the columella is 

 usually well developed in both. But hyades lacks the radial costal 

 ridges on the exotheca and the bounding polygonal grooves between 

 the ealicles. The differences in sections are very marked. However, 

 there are places, near the base, where the exotheca becomes more cel- 

 lular in this species, and in sections of the under side it is composed 

 of angular exothecal cells separated by thin dissepiments only. 



In some respects this species is intermediate between Solenastrma 

 and Orblcella, and raises the doubt whether a larger series might not 

 , compel us to unite the two genera. 



I have seen no specimens truly intermediate between this and 

 hyades, and as they can be distinguished by structural characters 

 generally held to be generic, it is necessary to keep them separate 

 here, but they may eventually prove to be one species. In that case 

 Solenastrcea cannot be maintained as a distinct genus. 



From O. annidaris and var. stellulata it can at once be distin- 

 guished by the thinner and much less projecting septa, and by the 

 wider septa of the third cycle, which do not bend toward and join the 

 septa of the second cycle in those forms. 



Orbicella hispidula V., sp. nov. 



Plate XV. Figures 3, 3a, 3&. 



Coral an encrusting mass over 125™"^ across, and from 5 to 20""" 

 thick. The texture is rather solid and heavy, there being much solid 

 exotheca between the ealicles, which are rather far apart, the inter- 

 spaces being mostly equal to, and often exceeding, their diameter. 



The ealicles are round, regularly stellate, a little prominent, with 

 swollen, sloping, costate rims, much as in those of 0. anmdaris, which 

 they resemble in size, though distinctly larger. The septa are in 

 three ver^^ regular cycles : the twelve principal ones are wide, nearly 

 equal, all i-eaching the rather large columella ; their edges are per- 

 pendicular and finely, shai'ply serrate, with slender rough teeth, 

 which extend also over their prominent, obtuse or subtruncate sum- 

 mits, giving them a rough appearance under a lens ; their surfaces 

 are also rough or hispid with numerous conical grains. The septa of 

 the third cycle are narrow, straight, and usually reach about half- 

 way to the columella. 



