﻿458 BULLETIN 103, UNITED STATES NATIONAL MUSEUM. 



septa have subentire margins, the thinner septa have decidedly 

 dentate edges. Larger septa solid; the thinner ones, especially 

 those next to the last cycle, considerably perforate; septal faces 

 granulate. 



Synapticulae well developed, especially near the wall and near 

 the columella; very obvious near the inner fusion of the septal 

 groups. vSome thin dissepiments present. 



Columella rather coarsely trabecular, well developed, approxi- 

 matel}" one-third the diameter of a calice; upper surface sunken in 

 a shallow central fossa. 



Asexual reproduction by intercalicular budding. 



Locality and geologic occurrence. — Antigua, in the Antigua forma- 

 tion, at stations 6881, Willoughby Bay (type and paratypes); 6854, 

 Rifle Butts; 6856, south side of Friar's hill; 6888, one-half mile 

 north of McKinnon's mill, collected by T. W. Vaughan. 



Type.—^o. 325204, U.S.N.M. 



Paratypes.— '^o. 325205, U.S.N.M. (2 specimens). 



That Cyathomorpha hilli is very nearly related to CyathomorpJia 

 rocJiettina (Michelin) Reis, is shown by a comparison of the descrip- 

 tions and figures here presented. C. hrowni, the next species to be 

 described, differs from C. hilli by its prominent, acute costae, and 

 by its septa higher than the second cycle being more strongly differ- 

 entiated according to cycles. 



It gives me pleasure to attach the name of Mr. Robert T. Hill to 

 this handsome species. 



CYATHOMORPHA BROWNI, new species. 



Plate 12(), figs. 1, 1«, 17;. 



This species is similar to Oyatliomorplia hilli in the general aspect 

 of the corallum. It differs principally in having prominent, acute 

 costae corresponding to all except the last cycle of septa, to which 

 the corresponding costae are either very small or obsolete. 



The calices range from about 8 to 13 nmi. in diameter; average 

 size smaller than in C. hilli. 



In a calice 12.5 mm. in diameter there are 4 cycles of septa and 

 in some systems the fifth is complete but it is represented bj' small, 

 thin, rudimentary septa. Primaries and secondaries subequal; 

 tertiarieg and quaternaries shorter and thinner according to cycles. 

 All septa except the last cycle bear thickened paUform lobes. The 

 septa are thinner and the interseptal spaces relatively wider than 

 in C. hilli. 



Synapticulae present near the wall and near the inner ends of the 

 septa. Apparently some thin dissepiments present. 



Locality and geologic occurrence. — Antigua, in the Antigua for- 

 mation, stations 6888, one-half mile north of McKinnon's mill (type, 



