318 A, EF. Verrili— The Bermuda Islands; Coral Reefs. 
while the fronds are from 1 to 2 feet high, and terminate in very 
slender, tapering, fragile bianohes of various sizes and shapes. Its 
color in life is usually dark russet brown, but sometimes is light 
yellowish brown or orange-brown, or even umber-brown. 
169 
Figure 169.—Zodids of living Millepora ; P, Anthozoid or feeding polyp, m, its 
mouth; D, DZ, defensive zodids; C, coenenchyma; ec, ectoderm; en, endo- 
derm. Much enlarged, after Moseley. 
Figure 170.—Sertularia Gayi, much enlarged. Drawn by A. H. Verrill. 
When young it forms more or less thick encrustations on dead 
corals, shells, ete. Sometimes it completely encrusts the dead axis 
of a gorgonian, and then by the unequal shrinking and swelling of 
the gorgonian when dried, the crust of white coral usually breaks up 
into short, often bead-like fragments (var. moniliformis). A form 
(var. ramosa) with unusually well rounded and forked branches has 
been separated by many former writers as a distinct species, but 
intermediate forms are common. Quelch (Voy. Chall.) recorded it 
from Bermuda. We did not find at Bermuda the variety, or dis- 
tinct species (MW. plicata), with broad, flat, unbranched fronds, which 
is common in some parts of the West Indies. Quelch also recorded 
var. carthageniensis D. and M. from Bermuda. The hydroid 
nature of the zodids of this coral was first ascertained by Professor 
Louis Agassiz, in 1858,* and his discovery has since been confirmed 
by poe others, who have observed the zodids of Millepores in 
* Amer. Journ. Science, ii, Xxvi, p. 140,: 1858. Proc. Boston Soc. Nat. Hist., 
vol. vi, p. 864, 1858. 
