﻿GEOLOGY AXD PALEONTOLOGY OF THE CAXAL ZONE. 453l 



septal length could not be made, but 6 teeth within 0.7 mm. were 

 counted on the outer part of a septum. This would be more than 8^ 

 teeth to 1 mm. Synapticulae abundant. 



Columella not greatly developed; upper surface finely papillary. 



I collected at Crocus Bay, Anguilla, a suite of 22 specimens very 

 closely similar to the Porto Rican specimen. Several of these are 

 illustrated by plate 117, figure 3; plate 120, figures 3, 4; and plate 

 121, figures 2, 2a. The calice represented by plate 117, figure 3, is^ 

 4.25 by 6.6 mm. in diameter, and has 68 septa; the larger calice illus- 

 trated by plate 120, figure 3, is 7 by 9.5 mm. in diameter, and has 91 

 septa; the calico illustrated by plate 120. figure 4, is 5.5 by 7.3 mm. 

 in diameter, and has 64 septa; and one of those figured on plate 121, 

 figure 2a, is 4.5 by 6.3 mm. in diameter, and has 75 septa. 



Specimens of what seem undoubtedly to belong to the same species 

 were collected in the Culebra formation, station 6020c, near Las 

 Cascadas, by Doctof MacDonald and me. Some specimens are as. 

 much as 14 inches (about 36 cm.) tall, and over 12 inches (about 31 

 cm.) thick. A part of the surface and an enlarged view of the calices- 

 are represented by plate 121, figures 1, la. A calice 4 by 5.7 mm. 

 in diameter has about 72 septa. 



A specimen collected by Gabb in Santo Domingo and identified by 

 Pourtales as Siderastraea siderea ^ belongs to this species. The speci- 

 men has numerous thin, crowded septa; there are about 82 septa in a 

 calice 4.5 mm. \\ade and 6.5 mm. long. It is the property of the 

 Museum of Comparative Zoology, Harvard University. 



Localities and geologic occurrence. — Island of Antigua, Antigua for- 

 mation, Duncan's type; station 6888, one-half mile north of McKin- 

 non's Mills, collected by T. W. Vaughan. 



Porto Rico, Pepino formation, station 3191, 4 miles west of Lares,. 

 coUected by R. T. Hill. 



Canal Zone, Culebra formation, station 6020c, at Las Cascadas,. 

 collected by T. W. Vaughan and D. F. MacDonald. 



Island of Anguilla, Anguilla formation, stations 6893, 6894, 6966, 

 lower and middle beds, south and west sides of Crocus Bay, collected 

 b}' T. W. Vaughan. 



As has been remarked, S. silecensis Vaughan from Georgia and 

 Florida is very close to S. conferta. In cahces of the same size there 

 are more septa and the septa are more finely dentate in (S. conferta 

 than in S. silecensis. 



Family OULASTREIDAE, new family. 



Fungid corals with the superficial aspect of the genera belonging to 

 the family Orbicellidae. Coralhtes with distinct margins, usually 

 separated by intercoraUite areas that are crossed by confluent or 



1 Geol. Mag., new ser., dec. 2, vol. 2, p. 545, 1875. 



