A, E. Verrill—The Bermuda Islands; Coral Reefs. 233 
arranged. In general appearance it resembles JZ. hispida Dana.* 
(See Verrill, these Trans., xi, p. 127, pl. xxi, figs. 2-2c, 1901.) The 
type of the latter is in the Museum of Yale University. 
Orbicella annularis (Dana) Ver. Star Coral. Figures 85, 86. 
Astrea annularis and Heliastrea annularis of many writers. 
Orbicella annularis Verrill, these Trans., xi, pp. 94, 171, pl. xv, figs. 1, la, 
1901. Duerden, Mem. Nat. Acad. Sci., viii, pp. 564-566, pls. viii-x, figs. 
64-735, anatomy, histology. 
Orbicella acropora Vaughan, op. cit., p. 301, plates vi, vii, 1902. 
This coral grows both in the form of thick crusts, 2 to 4 inches 
thick, and in hemispheres up to 3 feet or more in diameter. It is 
found mainly on the outer reefs, but has often been obtained from 
those not far off Ireland Island. In life it is usually pale yellow, 
Figure 86.—Orbicella annularis; a, polyps partially expanded ; 6, in full expan- 
sion. From colored drawings by A. H. Verrill. 
yellowish brown, or greenish, due to zodxantbelle. It can be dis- 
tinguished from most others by its slightly prominent, circular 
calicles, about 4 inch in diameter (fig. 85). The polyps, when fully 
expanded, rise considerably above the rims of the calicles, as shown 
in fig. 86, 6. They have about 24 slender, short, unequal tentacles 
with a small white knob at the tip. The soft upper body and the 
tentacles in expansion are translucent, usually yellowish or greenish 
with white specks. 
It is common on the Florida reefs and throughout the West Indies, 
where it often grows to great size, sometimes forming masses 3 to 5 
feet in diameter. 
* M. hispida has wider and much more irregular and lacerate septal teeth, and 
the septa are more numerous and more spinulose laterally. 
