518 BULLETIN 100, UNITED STATES NATIONAL MUSEUM. 
increase at the end of the low anterior arch in the lateral line. The 
scales are armed very strongly by a sharply 3-angled spine, which 
is about two-thirds as high as the width of the scale; this spine from 
its widened base is directed upward and backward at an angle of 
about 65°, extending to a point directly above the hind margin of 
the scale; this main spine is preceded by one to three smaller im- 
bricate spinules; a single spinule is sometimes present above or below 
the median keel. In C. parallelus of comparable size there are three 
to five parallel rows of several spinules, which increase in strength 
along the median, keel much less abruptly posteriorly. The scales 
on the infraorbital ridge before middle of eye are in a single series 
and bear two or three spinous keels like the main one on the scales 
of the body; behind middle of orbit the scales of the infraorbital 
ridge are armed by a single, very strong, broad keel, the main spine 
of which is about one-third as high as the diameter of the pupil; the 
ridge ends in a single, hard, strong scale, pointed posteriorly, and 
bearmg a heavy, retrorse spine, which is preceded by a few small 
spinules; this spine extends backward to within its own length of 
the preopercular margin. The 12 scales on the median rostral ridge 
bear about three series of spinules, except the last one, which has only 
the strong median keel, composed of three spinules. The remaining 
scales of the head bear but a single keel, like that on the body scales; 
the spines on the ridges are greatly strengthened and enlarged; the 
height of the tip of the spines from the base of the occipital ridge 
is about half the diameter of the pupil, being twice as great as in 
C. parallelus. The four series of scales between the occipital ridges 
converge backward to the middle of a naked area lying before the two 
strong occipital scutes, which lie side by side, and represent the single 
weaker median scute of C. parallelus. The series of scales midway 
between the occipital and postorbital ridges is little enlarged; about 
three scales, larger than those surrounding them, extend backward 
from the orbital rim to the preopercular ridge (a similar series occurs 
in C. parallelus). The under surface of the head is completely 
covered by deciduous prickle-like scales. 
The second dorsal spine is weak and smooth. The length of the 
first dorsal base is contained 1.2 times in the interdorsal space, 2.4 
times in the postorbital length of the head. The first ray of the 
second dorsal fin is shorter than the pupil. The rays of the pec- 
toral fin are slender and weak; the filamentous outer ventral ray 
extends to the origin of the anal fin, and is equal in length to the 
postorbital region of the head; the other ventral rays are weak and 
short, not nearly reaching to the anus. 
Color pale brownish in alcohol, black over the coelom; pale 
greenish on head, becoming blackish on the opercles, about the 
