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BULLETIN OF THE BUREAU OF FISHERIES 
the vent, rising again to highest point oyer vent, notching on either side of peduncle, 
and breaking entirely at vent. 
Pigmentation. — The 12-millimeter whitefish is characterized by a large, very 
yellow yolk sac, and by much yellow diffused in subsurface streaks about the head, 
above the stomach, and in some specimens over the whole body, thus differentiating 
it from Leucichthys artedi in which this color is less intense and limited to the yolk 
sac. Chromatophores are distributed essentially as in the herring, but generally 
they are much larger, darker, and more regularly arranged, consisting of a few large 
black stellate spots on top of head and a few very small ones on sides, running into 
an unbroken double line of about 52 on dorsal aspect, which are very large and square 
ly stellate. Chromatophores appear on underside of head and continue in a line 
across yolk sac and on dorsal aspect of intestine to vent, numbering about 28 on each 
side. Few others are spread over yolk sac, and a double ventral series of about 17, 
similar to dorsal, is apparent behind vent. 
13 .5 -millimeter stage . — About 1 week old. Total length, 13.5 ; length to vent, 10.0 ; 
greatest depth, 1.6; diameter of eye, 1.25 millimeters. Embryonic marginal fin fold 
unchanged in shape from preceding stage, but now with slight suggestions of 5 dorsal 
fin rays in anterior part, pectorals very large; yolk almost completely absorbed. 
