2 U. S. BUREAU OF FISHERIES 
the yellow pike perch is the most abundant and important 
commercially.” 
The body of the yellow pike perch is rounded instead of being com- 
pressed, the greatest width being about three-fourths of the greatest 
depth. The body is elongate, not as elevated as it is in the yellow 
perch, the gr eatest depth being about one-fifth of the distance from the 
tip of the ‘snout to the base of the tail fin. The length of the head, 
from the tip of the snout to the hind margin of the gill cover, is con- 
tained about three and one-fourth times in the total body length, ex- 
clusive of the tail fin. The snout, measured from its tip to the 
anterior margin of the orbit, is contained about three and one-half 
times in the Teneth of the head, and is rather larger than the hori- 
zontal diameter of the orbit (the latter contained about four and 
one-half to five and one-half times in the head). The mouth is 
rather large, the gape extending to approximately under the middle 

Vic. 1.—Stizostedion vitreum. Yellow pike perch 
of the eye. The jaws are provided with brushlike bands of small 
teeth, and in addition some comparatively long canine teeth. The 
two dorsal fins are separated, the first consisting of 12 or 13 spines 
(frequently one or two spines more or less), while the second dorsal 
consists of 19 to 22 soft rays. The anal fin has two spines and 11 
or 12 soft rays. The dorsal begins over the base of the pectoral, 
and the base of the ventral fin is but a little distance behind. The 
anal is placed entirely under the second dorsal. The tail fin is 
forked. The scales are rather small, there being about 90 oblique 
rows from the gill opening to the base of the tail. 
The body is vof a yellowish color, blotched with darker shades. 
The second dorsal fins usually are spotted, the small spots frequently 
being arranged in more or less regular rows. The first dorsal is 
irregularly blotched or spotted, and there is always a definite dark 
blotch on the membrane connecting the last two or three spines. 
The blue pike perch was for merly considered a color variety of the 
yellow, but 1t never reaches so large a size and matures earlier. The 
body is grayish blue in color, w ithout yellowish mottlings, and the 
lower fins are bluish white instead of yellow. The eyes are larger 
and close set. 
2A Check-list of the Fishes of the Great Lakes and Tributary Waters, with Nomen- 
clatorial Notes and Analytical Keys, by Carl L. Hubbs. University of Michigan, Museum 
of Zoology, Miscellaneous Publications No, 15, July 7, 1926, p. 58. 
