SIXTY-TWO SPECIES OF FISHES FROM LAKE ERIE 
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head, large stellate subsurface ones on underside of brain, and 2 on dorsal ridge near 
caudal. There are subsurface chromatophores at base of pectorals and a double 
arrow-shaped series on underside in gill region. The underside of stomach region 
has 2 to 4 uneven rows of rather small, round chromatophores, becoming irregular 
and single from intestine to vent (about 17 in this single series). The large air- 
bladder patch is continued as a double line of subsurface chromatophores to vent, 
thence as a double line of smaller surface ones to end of body (about 16). A few 
Figure 49 —Notropis cornutus chrysocephalus, 7 millimeters. (Drawn from living specimen) 
appear on caudal. The oblique line over yolk sac of younger stages is represented 
by a very few (about 6) chromatophores in the same position across the stomach. 
The marking is considerably variable in individuals, especially that on lateral line. 
In some 7-millimeter specimens the line is completely marked by linear chromat- 
ophores, while in others of larger size only a few such spots appear, and in a few none. 
The dorsal marking varies likewise. In some specimens this aspect is colorless, while 
in others a double line of rather large chromatophores occurs toward the anterior 
end. 
7 .5-millimeter stage. — A very slight concentration at future location of dorsal and 
anal fins discernible; caudal still lophocercal, but with a few rays developed ventrally. 
8 .5 -millimeter stage. — Concentration greater in embryonic marginal fin-fold but 
no rays; fin fold, however, more pinched; notochord turned abruptly upward at 
caudal. 
10.5 millimeter stage. — All elements of dorsal and anal complete, and about half 
of dorsal rays developed; no sign of ventrals. 
11.0-millimeter stage. — Dorsal, 8; anal, 9; elements and fin-rays complete. Total 
length, 11.0; standard length, 9.9; length to vent, 7.0; greatest depth, 1.7; diameter 
of eye, 0.9 millimeter. Myomeres, 21 to vent plus about 17 behind. Air bladder 
constricted considerably. Ventrals apparent, but very small and unrayed, with 
embryonic marginal fin fold persistent beneath them from below constriction of air 
bladder to vent. 
Pigmentation. — The marking here is essentially as in previous stages. The 
snout, interorbital region, and top of head are covered with very large, roundish 
chromatophores. Subsurface series occur below brain and gill regions and very 
