234 A, E. Verrill—The Bermuda Islands; Coral Reefs. 
Orbicella cavernosa (Linn.) Ver. Great Star Coral. Fig. 87. Pl. xxxa, fig. 1. 
Astrea cavernosa, A. radiata, and A. argus of many writers. 
Orbicella cavernosa Verrill, 1864; these Trans., xi, pp. 102, 171, 189, 1901. 
Vaughan, Fossil Corals, p. 27, 1901. 
This fine coral is much less common than the last. It grows 
chiefly on the outer and most exposed reefs, where it forms hemis- 
pherical masses. I have seen a few small specimens from the inner 
reefs, 2 to 3 inches thick. The largest Bermuda specimen that I 
Figure 87.—Orbicella cavernosa, about natural size. Phot. by A. H. V. 
have seen is a dome-shaped mass, rather more than a foot in diame- 
ter, but it is said to grow much larger there, as it certainly does in 
the West Indies and Florida, where it is munch more common and 
reaches the diameter of 4 to 5 feet at least. According to Pourtalés 
it occurs in 10 to 15 fathoms, off Florida. 
It is also found as far south as Pernambuco, Brazil. It is one of 
the common fossil corals in the elevated reefs of many of the West 
Indian Islands. At Dominica Island it occurs in an elevated reef, 
near Rosseau, about 1,000 feet above the sea, from whence I have 
good specimens collected by A. H. Verrill, 1905. It has also been 
found fossil in the Devonshire formation of Bermuda (see p. 187). 
It is easily distinguished from O. annularis by the much larger 
calicles, which are usually .25 to .30 of an inch (6 to 9™™) or more 
in diameter, and by the more numerous septa (about 48). The 
columella is usually large. 
Plesiastrea Goodei Verrill. Star Coral. Figure 88. 
These Trans., xi, pp. 106, 172, fig. 1, pl. xxxi, figs. 1, la, 1901. 
This is, apparently, a rare species. I have seen but two Bermuda 
specimens, one of which, now in the American Museum, New York, 
was taken by Mr. Whitfield on one of the small inner reefs, off 
