484 
POPULAR SCIENCE REVIEW. 
well-marked species of Glupea ; and since a comparison of the 
characters of the G. alba and alosa is best made when their 
characters are placed side loj side^ we shall tabulate the dif- 
ferences in this manner, for the sake of perspicuity: — 
In the Young Shad : — 
The body is deep in proportion to the 
length. 
The colour of the back is bluish. 
The lateral line is feebly marked. 
The abdominal serrations are deeply 
cut, and much curved. 
The silvery internal membrane of the 
abdomen is unstained. . 
There is a series of dusky spots ex- 
tending from the gih-flap. 
The tongue is smooth and dark. 
The lower jaw has three strong teeth 
on the outer edge. 
The snout is bifid. 
The whole edge of the uj)per jaw is 
covered with teeth. 
The eye is comparatively small. 
The vertebrae in all shads, young and 
old, never exceed 55. 
The formula for the fin-rays is : — 
D. 20, P. 19, Y. 12, A. 21, tad 
26. 
In the Whitebait — 
The body is not so deep in proportion 
to length. 
The colour of the back is a greenish- 
O 
ash. 
The lateral line is clear and distinct. 
The abdominal serrations are not so 
deeply marked, and are less 
curved. 
The silvery membrane is stained with 
black pigment. 
There is no trace of spots. 
The tongue is rough and white. 
The lower jaw has no teeth upon the 
outer edge. 
The snout has no notch. 
Portion only of the upper jaw is 
covered with teeth. 
The eye is comparatively large. 
The vertebrae are invariably 56. 
The formula for the fin-rays is : — 
D. 17, P. 15, V. 7, A. 15, tail 
20 . 
Besides the foregoing^, there are differences, of course more 
or less relative, in the form of the dorsal fins and in the num- 
ber of the csecal appendages, which of themselves alone would 
be sufficient to warrant a distinction between the whitebait 
and the shad. 
It may however be remarked, that although it is certain the 
whitebait is not the young of G. alosa, it is not certainly proved 
that it is a perfect species : it may be distinct from the shad, 
and yet may be the descendant of some other members of 
the genus Glupea. To us it appears not improbable that 
