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BULLETIN OF THE BUREAU OF FISHERIES 
Pigmentation. — A broad band of black chromatophores extends from tip of 
snout to end of body, terminating in a black spot at base of caudal and extending 
out on to fin. The head and dorsal aspect of body are covered with small chroma- 
tophores extending down to meet the lateral band (not so in R. cataradse). Sub- 
surface chromatophores are heavy on dorsal aspect of intestine and a double series 
(4 chromatophores wide around anal base) occurs on ventral ridge. All fins are 
marked. No black is evident on lower lip as in Semotilus atromaculatus. 
BREEDING 
The black-nosed dace is a spring spawner, seeking the upper courses of streams 
over clean gravel. During the breeding season the males have the lateral band, 
lower fins, and sometimes the whole body colored bright crimson. 
15. Rhinichthys cataractse (Cuvier and Valenciennes). Long-nosed dace. 
RECORD OF CAPTURE 
One young 18.5-millimeter specimen was taken at the mouth of Eighteen Mile 
Creek on July 18, 1928, and another 12.5 millimeters long on June 29, 1929, in a foot 
net towed in 3 feet of water off Crystal Beach. Adults are very common along the 
lake shore, especially over rocky bottom and in the lower courses of nearly all streams 
of the region, but this species does not seek the headwaters as does atronasus. 
DESCRIPTION 
The young are characterized by a dusky lateral band and caudal spot which 
does not extend out on to the fin as in R. atronasus lunatus. This band fades in the 
adult. The protruding snout of the later stages is evident even in these small 
specimens. 
18. 7 -millimeter stage . — Total length, 13.7; standard length, 12.2; length to vent, 
8.5; length of head, 3.1; diameter of eye, 1.0; snout, 0.85; greatest depth before 
vent, 2.3; depth behind vent, 1.6; length to dorsal, 6.3 millimeters. Myomeres, 22 
to vent plus 15 behind. Dorsal I, 7; anal I, 6; ventrals well developed. Body 
elongate; mouth small, with protruding snout characteristic of later stages evident 
but not pronounced, lower jaw included. 
Pigmentation. — This species is characterized by a dusky lateral band forming a 
small spot at base of caudal, but this is much fainter than in R. atronasus, Semotilus 
atromaculatus, and others. (Lateral band is obsolete in adult.) Chromatophores 
occur on top of head, along dorsal ridge, and ventral ridge from vent to caudal, and 
