SIXTY-TWO SPECIES OF FISHES FROM LAKE ERIE 
309 
and notching at peduncle; ventrally starting beneath yolk sac, breaking completely 
at vent, and notching at peduncle; caudal lophocercal; pectorals large, rounded. 
Head very blunt, its highest point over posterior part of eye; mouth subinferior, jaws 
equal. 
Pigmentation. — The larval Leucichthys artedi is opaque white in color, differing 
from Coregonus clupeajormis in the restriction of yellow color to the yolk, whereas 
in the latter this color is diffused in subsurface streaks about the head, above the 
Figure 6 . — Leucichthys artedi, 12.5 millimeters 
stomach, and in some specimens over the whole body. In the specimen figured, 2 
round areas of chromatophores appear on head followed by a double series of 18 along 
dorsal aspect to a point opposite vent, thence 24 to tip of tail. These two lines are 
not even, the chromatophores being sometimes alternate and differing in size and 
number, thus distinguishing the species from Coregonus clupeajormis in which the 
dorsal series usually are perfectly symmetrical . Lateral and ventral aspects of head 
are colorless. One very large stellate spot is apparent over pericardiac region at the 
beginning of the yolk sac. Behind this, two more or less definite lines extend across 
sac, and a few chromatophores, very linear in shape, are arranged longitudinally on 
underside of sac. Starting just before end of yolk sac, a series of about 20 large 
Figure 7 . — Leucichthys artedi, 14.5 millimeters 
stellate chromatophores occurs over intestine, and behind vent there is an uneven 
double line of about 12 intersprinkled with smaller ones to tip of tail. 
12. 5 -millimeter stage. — Total length, 12.5; length to vent, 8.5; greatest depth, 1.6; 
diameter of eye, 1.0 millimeter; myomeres, 38 to vent plus 19 behind. Immediately 
after preceding stage yolk beginning to shrink, and at this stage represented by only 
a fragment showing yellowish through the body wall. Embryonic marginal fin fold 
unchanged; pectorals enlarged; notochord turning upward very slightly. Head less 
blunt than before; lower jaw slightly shorter. 
Pigmentation.— The linear chromatophores on underside of yolk sac now are 
more numerous, giving a “pin feather” effect, and those on sides of sac have increased 
greatly in size and are remarkably stellate in shape; others appear unchanged. All 
specimens which have been examined show heavy dorsal pigment on head and at the 
beginning of dorsal ridge, then a break occurs in the series until shortly before vent 
during which space the chromatophores are quite sparsely distributed. Following 
the break they are closer together, more numerous, and form a very distinct band. 
