SIXTY-TWO SPECIES OF FISHES FROM LAKE ERIE 
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the later characters of the adult evident especially in contour of head and mouth; 
barbel represented by a large fleshy protuberance; intestine open at margin of body; 
ventrals apparent below pectorals; deep notching of marginal fin fold marking out 
position of the two dorsals, and most of dorsal, anal, and caudal rays indicated. 
Body ending in a straight point forming an isocercal tail. 
Pigmentation. — Chromatophores are confined to the subsurface patch above 
stomach region and about 25 rather large roundish black spots distributed over 
top of head, followed by subsurface chromatophores hardly discernible over anterior 
part of notochord (possibly continuing for its entire length). 
l^-.O-millimeter stage . — Total length, 14.0; standard length, 13.2; length to vent, 
7.0; greatest depth, 2.75; diameter of eye, 1.0 millimeters. This stage differs from the 
adult in slightly shorter upper jaw. Marginal rays entirely formed at this stage, and 
sections of embryonic fin persist to connect caudal with dorsal and anal fins; ventrals 
larger and completely rayed. 
Pigmentation. — A few stellate chromatophores occur on both jaws, followed by 
very distinct preorbital, postorbital, and opercular patches which give the impression 
of a lateral pigment band on either side of head. Many large chromatophores are 
massed over top of head. Lateral line is marked by a single broken series of large 
chromatophores extending to the extreme caudal region, becoming wider with more 
numerous and smaller subsurface spots toward the end. Dorsal aspect has numerous 
pigment spots arranged irregularly in 10 to 12 groups, each one consisting of a double 
row of large, close-set chromatophores outlining dorsal fins and others more sparsely 
distributed extending halfway to lateral line. Although the breaks in dorsal and 
lateral series do not necessarily coincide, a somewhat banded impression is given, 
emphasized in older specimens. 
19.0-millimeter stage . — Total length, 19.0; standard length, 17.0; length to vent, 
9.5; greatest depth, 3.15; diameter of eye, 1.2 millimeters. Characters essentially 
same as in preceding stage, except for completely formed fins and barbel, and 
intensified pigmentation. The identification of these postlarval and young-fish 
