342 BULLETIN" 103, UNITED STATES NATIONAL MUSEUM. 



Calices shallow, fairly large, 1 mm. in diameter; usually 1 mm. 

 apart. Margins not elevated; the walls barely distinguishable from 

 the surrounding coenenchyma. 



Septa in two distinct cycles; only the six primaries reach the 

 columella, but the secondaries are well developed. 



Columella, a pointed style. 



Coenenchymal surface crossed by costules, along which are rela- 

 tively coarse granulations. In places the coenenchyma appears cel- 

 lular, as the costules are not solidly fused but have cellules developed 

 between them. 



Locality and geologic occurrence. — Canal Zone, station 6016, in the 

 Emperador limestone, quarry, Empire, collected by T. W. Vaughan 

 and D. F. Macdonald. 



Type.— No. 324775, U.S.N.M. 



This species most closely resembles a species from the base of the 

 Chattahoochee formation, on Flint River, 4J miles below Bainbridge, 

 Georgia, but it differs from the latter species in two characters, 

 namely, the outer ends of the principal septa are not produced into 

 prominent teeth, and in places the coenenchyma is distinctly cellular. 



STYLOPHORA PONDEROSA Vaughan. 



1900. Stylophora ponderosa Vaughan, U. S. Geol. Survey Mon. 39, p. 132, pi. 

 13, fig. 16; pi. 14, figs. 1, la, 16. 



One of the specimens obtained by me in Antigua seems referable 

 to this species. The upper surface has four nipple-shaped elevations 

 on it; the largest is about 15 mm. in diameter at the base, about 

 5 mm. tall, and about 5 mm. in diameter just below the rounded 

 summit. Except such protuberances, the surface is nattish, with 

 some undulations. The size of the calices and the septal characters 

 are as in the cotypes of S. ponderosa. 



Localities and geologic occurrence. — Alabama, Salt Mountain, 6 

 miles south of Jackson, just above the top of the Vicksburg group, 

 collected by T. W. Vaughan. 



Antigua, station 6854, Rifle Butts, in the Antigua formation, 

 collected by T. W. Vaughan. 



Genus POCILLOPORA Lamarck. 



1816. Pocillopora Lamarck, Hist. nat. Anim. sans Vert., vol. 2, p. 273. 

 1918. Pocillopora Vaughan, Carnegie Inst. Washington Pub. 213, p. 75. 



Type species. — Pocillopora acuta Lamarck. 



Duncan described two fossil species of Pocillopora from the West 

 Indies, P. crassoramosa i from the Nivaje shale of Santo Domingo, 

 and Pocillopora tenuis 2 from Antigua. I have seen good suites of 



1 Geol. Soc. London Quart. Journ., vol. 20, p. 40, pi. 5, figs. 2a, 26, 1864. 

 Idem, vol. 24, p. 21, pi. 1, figs. 5a, 5&, 5c, 1SR7. 



