524 BULLETIN 100, UNITED STATES NATIONAL MUSEUM. 
portion of the head; the outer ventral ray, with its filament, extends 
to the front of the peritroct, and is contained 1.9 times in the head; 
the inner ventral rays are not quite half as long as the orbit, and 
extend but halfway to the origin of the anal fin, the vertical from 
which passes behind the first dorsal a distance half as long as the 
fin itself; the height of the first anal ray and of the orbit are equal. 
The trunk is silvery between the anus and the ventral bases and 
on an area extending thence forward along the sides of the isthmus 
and upward to the middle of the sides; this silvery region is con- 
tinued backward as a streak occupying the middle third of the sides 
of the tail; the abdominal region before the ventral fins has a cop- 
pery luster; the immediate bases of the paired fins are blackish; a 
fine black ring surrounds each of the Jens-shaped structures on the 
belly; the rest of the body is brownish, becoming dark below the 
first dorsal fin. The markings of the head consist of a dark brown 
region about the occiput; a dark streak along the margins of the 
postorbital sensory canals, and narrow black streaks along the front 
margin of the snout, along the inner margins of the lips, and along 
the sides of the central canal in each mandibular ramus. The sides 
of the head are bright silvery, but the black lining of the branchial 
cavity shows through the opercle. The membranes over the sensory 
canals are transparent, allowing the coloration of the walls of the 
canals to be visible; the vertical wall of the suborbital cavity is 
silvery, but its roof is dark; the floor of the interorbital cavity is 
blackish. The buccal and branchial cavities are lined with silvery 
everywhere excepting a margin about as wide as the pupil on the 
outer posterior sides of the branchial cavity; this dark is margined 
at. the extreme edge of the opercular and branchiostegal membranes 
by a whitish line. The parietal peritoneum is silvery with some 
diffused brownish color and black spots. 
The “striated” region of the belly consists of a strip, about as 
wide as the pupil, extending along the sides of the isthmus and 
backward to above the base of the ventral fin, from which place the 
striae fade out posteriorly, being traceable about halfway to the 
anus. The striae are similar to but more extensive than those of 
tenuis, they are finer than those of striatisstmus, and do not occur, 
as in that species, on a thickened portion of the skin below the post- 
clavicle. The end of that bone is much nearer the base of the ven- 
trals than the anus, the reverse of its position in striatissimus. The 
gular membrane lacks the median black streak of striatulus, and 
lacks the double striation characteristic of st7iatéssimus,; it is marked 
only by numerous black lines somewhat coarser than those on the 
striated region of the belly. 
