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BULLETIN OF THE BUREAU OF FISHERIES 
deciduous in young and to a lesser extent in the adult; ventral scutes, 20 to 24 in advance of ventrals 
(usual number 21 or 22) and 12 to 16 behind ventrals (usual number 14 or 15), total number of 
ventral scutes 32 to 39 (usual number 35 to 37) ; dorsal fin rather small, its outer margin slightly 
concave, the origin considerably nearer tip of snout than base of caudal; caudal fin deeply forked, 
both lobes pointed; anal fin somewhat longer than the dorsal, the anterior rays only slightly longer 
than the posterior ones, its origin at least twice the diameter of the eye behind vertical from the 
end of the dorsal; ventral fins rather small, pointed, inserted a little in advance of the vertical 
from middle of base of dorsal; pectoral fins much larger than the ventrals but similar in shape, 
1.4 to 1.7 in head. 
Color greenish, With metallic luster above, sides silvery; a dark spot at shoulder, occasionally 
followed by smaller ones, rarely with a second parallel row somewhat above the median line of 
side. Fins all pale to slightly greenish, the dorsal and caudal somewhat dusky in the larger speci- 
mens, darkest at tips. Peritoneum pale. 
Leim (1924, p. 224), who made an exhaustive study of the shad in the Bay of Fundy, gives 
the following counts for rays, scutes, and vertebrae (the predominating numbers are placed in 
parentheses): Dorsal rays 15 to 19 (17 or 18), 676 fish; anal rays 18 to 24 (20 to 22), 317 fish; 
pectoral rays 14 to 18 (15 to 17), 287 fish; pelvic (ventral) rays 8 to 10 (9), 277 fish; anterior ventral 
scutes 19 to 23 (20 to 22), 315 fish; posterior ventral scutes 12 to 19 (16 or 17), 653 fish; vertebrae 
51 to 59 (56 or 57), 170 fish. These counts vary somewhat from those taken of Chesapeake Bay 
shad. This, however, is only to be expected, as Leim, who examined a large number of fish, found 
a slight variation even among the several localities of the Bay of Fundy where his specimens were 
obtained. 
Numerous small specimens, 21 to 115 millimeters ( 5 /e to 4)4 inches) in length, taken in fresh 
water, are at hand. We also have 26 specimens contained in various small lots, of different local- 
ities and dates, taken in salt or brackish water during the fall and winter, ranging from 97 to 243 
millimeters (3% to 9)4 inches) in length, and three adult females. The young shad is not readily 
distinguished from the young of the genus Pomolobus. It is particularly close to the hickory shad, 
( P . mediocris ), from which the young are difficult to separate. In the common shad the lower 
jaw, however, is included in the upper; it does not protrude and it does not enter into the dorsal 
profile. In the hickory shad the lower jaw projects strongly and the tip of it enters into the 
dorsal profile. Another and more pronounced difference is evident in the number of gill rakers 
supported by the lower limb of the first arch. The number of gill rakers increases greatly with 
age in at least some of the Clupeidae, but in our series there is no overlapping, the common shad 
always having more gill rakers than the hickory shad. The range in the number of gill rakers on 
the lower limb of the first arch for the common shad in specimens ranging from 1)4 to 23 inches 
in length is 26 to 71. In the hickory shad in specimens 6)4 to 12 inches long it is from 18 to 22. 
The difference is more evident when specimens of the same size are compared. A common shad 
160 millimeters long, for example, has about 40 gill rakers on the lower limb of the first arch, whereas 
a hickory shad of the same length has only about 18. From the other species of Pomolobus the 
