288 A. FE. Verrill—The Bermuda Islands; Coral Reefs. 
the upper third or fourth part, which is smoother and naked, so 
that the surface is usually divisible into two regions, usually with a 
constriction between, and with a secondary sphincter muscle corre- 
sponding to it ; but this difference is not always evident externally. 
In many contracted specimens small irregular verruce and trans- 
verse ruge occur about the middle of the column, where the wall 
appears to be thickest. The mesenteries sometimes show through 
the column, where thin distally, as longitudinal lines. 
The two sphincter muscles agree well in sections with the figure 
of Erdmann (op. cit., pl. v, fig. 2). 
The polyps are united into more or less extensive clusters either 
by slender narrow stolons, or by flat expansions of caenenchyma, or 
directly, the buds often springing from the basal regions of the 
column, or even from higher up on the sides ; sometimes stolons 
also arise from above the base (fig. 133). These variations may all 
occur in one colony. 
The polyps may be crowded or openly grouped, but seldom if ever 
wide apart, as in sociatus. According to Hertwig and Erdmann 
their Bermuda specimens were hermaphrodite. 
134 135 
Figure 134.—Zoanthus proteus ; part of a large colony in contraction, about % 
nat. size. 
Figure 135.—Zoanthus proteus; a, pedunculate form; 6, ordinary forms; c¢, 
short forms, all from one colony. x1}. Drawn by A. H. V. 
Tentacles numerous, slender, usually 48 to 52, green or yellow. 
Color of column distally is olive-green, sometimes bluish or tur- 
quoise-blue ; disk pale ochre-yellow, with white specks, sometimes 
green, with paler radial lines. 
