dl. BE. Verrill—The Bermuda Islands; Coral Reefs. 303 
numerous forking branches arising from a stout basal trunk. The 
branchlets have a tendency to stand somewhat in one plane, so that 
the group is flattened ; they curve outward at base and then become 
rather rigidly erect, with blunt tips. They are usually more or less 
crooked or wavy, and vary in length up to 6 to 8 inches or more, 
and when well grown have a diameter of about 5 to 7™™. The 
calicles are small, often almost punctiform, pretty evenly scattered 
over the whole surface, about 1™™ apart. They are usually slightly 
8-rayed, and when fully contracted are level with the ceenenchyma 
or may even be a little sunken, but frequently, in less strongly con- 
tracted specimens, they are slightly raised on low mammilliform 
elevations, and then the pores are larger, up to about .5™™, as in 
fig. 147, b. 
The color, in life, is almost always dark purple or purplish brown, 
but when dried, under identical conditions, part of them will remain 
purple, others become reddish brown, and many become brownish 
yellow, russet, or fawn-color, but no other differences could be found. 
The polyps are small, but quite prominent (see pl. xxxiis, fig. 2, 
b, ce), nearly translucent, with rather long, delicately pinnate tenta- 
cles. 
The axis of this was also analyzed by Prof. Mendel and Mr. Cook, 
for iodine, etc. It contained a larger percentage of iodine than any 
other species tested: 4.95 per cent. of the water-free substance in 
one case. 
It is doubtful if this be the true flewwosa of Lamouroux, which 
was described as a yellow species, like P. mutica D. and M. I have 
personally seen no bright yellow variety of this species, and think it 
possible that flewwosa may be a distinct species. But this is the P. 
flexuosa of most recent writers, and therefore it seems best to retain 
that name until the yellow form can be reexamined microscopically. 
This is the true P. anguiculus of Dana, and that name should be 
used if flexuosa proves to be distinct. 
It is a common species on the Florida Reefs and is found through - 
out the West Indies, south to Dominica. 
Plexaura Valenciennesi Wright and Stud., Voy. Chall., Zodl., vol. xxxi, p. 
137, pl. xxxiii, fig. 1 (spicules). 
Plexaura flexuosa Val., MSS., Edw. and H., Corall., iti, p. 154 (non Lamx., t. 
Wr. and Studer). 
This species was described from a single specimen dredged in 
shallow water. It was about 10 inches high, dichotomous, with the 
