SIXTY-TWO SPECIES OF FISHES FROM LAKE ERIE 
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long, slender, sharply compressed body, without elevation of back; very oblique 
mouth with upper lip on level of upper part of pupil; rather large eye; decurved 
lateral line; and position of dorsal fin, indicated by a concentration in the marginal 
fin fold beginning over the seventeenth myomere, identical with the position of the 
dorsal in adults of that species. 
Pigmentation. — At this stage there are about 12 large black chromatophores 
on top of head, with no other dorsal coloration. Chromatophores occurring over 
air bladder and dorsal aspect of intestine are farther imbedded through the growth 
of the larva and thus are less evident. The chromatophores seen in previous stages 
along the ventral aspect of intestine have disappeared, with the exception of a very 
large one just before vent; this one ventral spot is conspicuous in the next stage 
described and figured. At the posterior end of body the ventral line chromatophores 
follow the notochord upward. Starting just before the vent, a single series of about 
9 linear chromatophores marks the lateral line. 
10.5-millimeter stage . — Total length, 10.5; standard length, 9.5; length to vent, 
6.7; length of head, 2.0; snout, 0.43; diameter of eye, 0.7; greatest depth before vent, 
1.64; depth behind vent, 0.95 millimeter. Myomeres, 22 to vent plus 16 behind. 
Marginal fin fold has disappeared dorsally before the origin of permanent dorsal at 
about the sixteenth myomere. Dorsal definitely shaped with elements and eight 
partially-formed rays evident. Embryonic fin persisting behind dorsal as a narrow 
marginal band continuous with the heterocercal caudal; caudal rays formed but 
distal margin only slightly emarginate. Embryonic marginal persisting ventrally. 
Pigmentation. — Chromatophores occur as in preceding stages with additional 
surface spots on snout and caudal, and subsurface spots in gill and isthmus regions, 
over 1 -chambered air bladder, along dorsal aspect of notochord, and at end of body 
forming a caudal spot. 
13.5-millimeter stage . — Total length, 13.5; standard length, 11.5; length to vent, 
8.0; length of head, 3.0; snout, 0.7; diameter of eye, 0.81; greatest depth before 
vent, 2.0; depth behind vent, 1.5 millimeters. Myomeres, 22 to vent plus 16 behind. 
Dorsal, 8; anal, 11, completely formed; only tiny portion of embryonic fin fold behind 
