836 
BULLETIN OF THE BUREAU OF FISHERIES 
The larval striped bass at 144 hours after fertilization of the egg reaches about 
5.8 mm in length. The mouth parts and digestive tract become better developed 
preparatory to feeding. A series of small chromatophores now extends along the 
ventral edge of the entire yolksac. (See fig. 12.) 
The larva at 192 hours after fertilization of the egg has the oil globule and yolksac 
nearly absorbed. The length of the fish increases only slightly, to about 6 mm. 
Pigmentation on the ventral surface of the body becomes stronger. (See fig. 13.) 
Figure 15.— Striped bass young 240 hours after fertilization of egg; length 9 millimeters; food available to fish. 
The larva at about 288 hours after fertilization of the egg, about 6 mm in length, 
commences to die rapidly in an aquarium not supplied with food. No fins have 
developed on the fish except the pectorals. The finfold still extends from the region 
of the head around the body to the abdomen, becoming interrupted at the vent. A 
more or less continuous line of pigmentation extends along the ventral portion of the 
body from the opercle to a point about midway between the vent and the tail. A 
large chromatophore lies on the upper surface of the swim bladder. (See fig. 14.) 
Figure 16. — Striped bass young 18 days old; length 13 millimeters; reared in aquarium at Edenton, N. C., May 1937. 
The young striped bass reach a post-larval stage at 240 hours after fertilization 
of the egg provided food is made available. At 9 mm in length the postlarva has lost 
most of the larval finfold. The second dorsal and anal finrays become slightly differ- 
entiated although the first dorsal and ventral fins are wanting. Large chromato- 
phores are scattered profusely on the top of the head and a series of branching chro- 
matophores run along the ventral edge of the body from the head to the tail, becoming 
interrupted along the intestine and the vent. A regular but broken line of pigmenta- 
tion extends medially along the side from the pectoral fin to the base of the tail. 
Mouth parts are well developed. (See fig. 15.) 
The postlarva at 13 mm (one-half inch) in length, 18 days after fertilization of the 
egg, has the dorsal and anal finrays well differentiated. The spinous and soft dorsal 
fins are still connected by the finfold and the spines are still quite rudimentary. The 
