FOURTEEN TELEOSTEAN FISHES AT BEAUFORT, N. C. 
461 
Ventral fin folds now are slightly in evidence. The rays in the soft dorsal, caudal, 
anal, and pectorals are becoming differentiated, the ray development having pro- 
gressed somewhat further in the pectoral and caudal fins than in the other fins 
mentioned. The notochord still is visible in the upper part of the base of the rounded 
caudal fin, but the tail has lost much of its heterocercal character possessed at a 
somewhat earlier stage. The spinous dorsal still remains largely undifferentiated. 
Pigmentation is more diffuse than in smaller fish, although some large and distinct 
chromatophores remain present much as in 5-millimeter fish. A dark lateral stripe 
is present on most of the caudal length of the body. Then there is also a concen- 
tration of color under the base of the dorsal and anal fins. We have specimens 
preserved since 1914 which are entirely without dark pigment. It is probable, 
though, that these fish have faded and that the general dark color described in the 
foregoing lines is normal (Fig. 75.) 
The cluster of large, black chromatophores now present at the nape is of much 
value in recognizing amberfish of this size. This is especially helpful since the other 
color markings are largely similar to those of the scad of the same size. This cluster 
of black chromatophores persists until a length of at least 14 millimeters is attained. 
At that size fin rays are 
developed and identifi- 
cation may be based 
largely on adult char- 
acters. 
Specimens 10 milli- 
meters long . — The body 
is regular in outline, 
elongate, compressed, 
and shaped much as in 
. Figure 75 . — Seriola dumerili. Drawn from a specimen 5.7 millimeters long 
the adult, except that it 
is less robust. The fins are all fully differentiated and the soft rays are well developed. 
It is still difficult to enumerate the rays in the dorsal and anal, because of the crowded 
condition. The anal spines are short and distinct. The spines in the first dorsal, how- 
ever, are not fully differentiated and the fin, although connected with the second dorsal, 
is distinct because it is lower. The caudal fin, round in somewhat smaller fish, has 
an almost straight margin at this size. In the specimens at hand, preserved in 1914, 
the body is quite dark brownish in color with scattered darker chromatophores. 
The dark lateral stripe or line of smaller fish has become less distinct and the con- 
centration of black chromatophores at the base of the dorsal and anal fins are no longer 
pronounced. The dorsal surface of the head is profusely dotted with black. 
Specimens 12 to 14 millimeters long . — The changes since a length of 10 millimeters 
was reached are not pronounced. At a length of 12 to 14 millimeters the rays of 
the dorsal and anal fins, although crowded, have become distinct enough for enumer- 
ation, and the caudal fin is decidedly concave. Preopercular spines are still prom- 
inent although proportionately smaller than in somewhat smaller fish. In specimens 
stained and mounted the vertebrae may be fairly accurately enumerated, the number 
being 11 + 14 to 16. This count agrees fairly well with the single adult dissected 
which had 10 + 14 vertebrae. The last caudal vertebra (hypleural) in 12-millimeter 
fish is not yet fan shaped as in the adult, for it is pointed and curved upward distally, 
therefore retaining in a measure the heterocercal character of younger fish. The color 
remains essentially as in 10-millimeter fish. (Fig. 76.) 
2698—30 6 
