346 
BULLETIN OF THE BUREAU OF FISHERIES 
The influence of artificial rearing upon the normal growth of the larva was evident 
with these specimens. One little fish was kept living for 10 weeks during which time 
it fed actively on prepared crushed insect food. The fins and other adult characters 
developed normally, but the young fish grew only to a length of 10 millimeters. 
Under natural conditions it would undoubtedly have been very much larger. 
12 .0-millimeter stage . — Total length, 12.0; standard length, 10.25; length to vent, 
7.0; length of head, 2.6; snout, 0.45; diameter of eye, 1.0; greatest depth before vent, 
1.6; depth behind vent, 1.0; length to dorsal, 5.5; to anal, 7.1 millimeters. Myomeres, 
Figure 57 . — Hyborhynchus notatus, 1 week old, 6 millimeters. (Drawn from living specimen) 
21 to vent plus 15 behind. Characterized by abruptly decurved snout, inferior hori- 
zontal mouth with lower jaw included; slender body and somewhat depressed back; 
slender caudal peduncle; light peritoneum (although in 17.75-millimeter specimen 
quite dark). Dorsal I (rudimentary), 8; anal I (rudimentary), 7. 
Pigmentation. — The 12-millimeter specimen is characterized by a black spot 
at base of caudal as in many cyprinids, and the fact that although diffuse chroma- 
tophores over snout and cheek suggest a band, the real lateral band starts most 
decidedly behind the head and is less conspicuous than in the other lateral-banded 
cyprinids. Chromatophores occur also on top of the head and along the whole dorsal 
aspect in irregular longitudinal rows, more concentrated at base of dorsal and below 
the surface dorsafly on the intestine. Many are grouped on surface around base of 
anal and thence in a double row to base of caudal. A few appear on pectorals and 
caudal. Sides of body, except for lateral band, and belly are colorless. 
Young adult stage. — Dorsal, 9 (first ray enlarged); anal, 7; caudal forked; ventrals 
midway between pectorals and anal. Total length, 17.75; standard length, 14.5; 
