BLUE SHARK. 
effect of age, but is to be perceived in Sharks in the earliest 
stage of their growth. 
The largest I have heard of, but not seen, was upwards oi 
fourteen feet long, but the more ordinary size is from six to 
eight feet in length; the body round and slender, tapering 
towards the tail. Head flat on the top, snout depressed, pro- 
jecting; the mouth far beneath, well furnished with strong, flat, 
triangular teeth, the points inclining inward, the edges serrated. 
Nostrils a good distance from the mouth, and not lobod; gill 
openings flve, near the root of the pectoral fln. Skin but 
slightly rough; pectoral fins large and long, although not pro- 
portionally so much so as is represented in Lacepede’s figure 
of his smooth-toothed Blue Shark, vol. i., pi. 9, f. 1; and which 
therefore, if correctly represented, will be an additional mark 
of distinction between the two species. These fins are placed 
low on the body in all Sharks, and in the Blue Shark end in 
a point. The ventrals small; the anterior border of the first 
dorsal fin begins midway between the snout and root of the 
tail; the second dorsal opposite the anal. The upper lobe of 
the tail moderately long, with a notch, as in most Sharks, near 
the end; at its root also, where it joins the body, a deep 
depression, but I have known this wanting. The upper parts of 
the body and fins blue, the belly white 
INSIDE VIEW or THE TEETH. 
UPPER TEETH. 
