SELACHII. 289 



cutting teeth, most generally serrated on the edges, their first dorsal is considerably 

 before the ventrals, and the second one opposite to the anal. They are destitute 

 of spiracles, the nostrils are under the middle of the depressed snout, and the pos- 

 terior gill-openings are over the pectorals. The Common or White shark, the 

 terror of all seas, attains the length of thirty feet, and may be recognised by its 

 teeth, which, in the upper jaw, are in form of an isosceles triangle with rectilinear 

 sides and jagged or serrated edges ; in the lower jaw they have a narrow point 

 upon a broader base. The rows of teeth are said to increase with the age of the 

 fish, which, when adult, has six distinct ranges, the outer teeth being then two 

 inches and a half long. This shark has a flat head, and a round depressed snout 

 projecting beyond the mouth, which is underneath the head. The pectoral fin is 

 large, as it very frequently is in fishes which have large heads and mouths so 

 situated. 



[120.] 2. Squalus (Carcharias) Terr^e-nov^e. (Richardson.) 



Newfoundland Shark. 



Green-backed shark {Squalus ptmctatus). Mitchill, i., p. 483 ? 



I am indebted to Mr. Audubon for a small and apparently young specimen of 

 this shark. It is closely allied to the carcharias glaucus by the form of its teeth, 

 which are not however serrated, at least in the young state, and its pectorals can- 

 not be said to be very long and much pointed like those of the Blue shark. The 

 Green-backed shark of Mitchill agrees with ours in the teeth not being serrated, 

 but his description is not particular enough to enable us to say that they are the 

 same species. 



DESCRIPTION 

 Of a specimen taken at Newfoundland. 



Form. — Head, and particularly the snout, broad and depressed, the latter rounded at the 

 tip : the breadth of the head between the eyes is about half its length, and at the nape about 

 two-thirds. The body tapers considerably, is much compressed posteriorly/ and the tail, ex- 

 clusive of the fin, is thin and narrowly lanceolate. There is a narrow, oblong, flattened space 

 between the second dorsal and caudal, which, in the squalus glaucus, is said to be triangular ; 

 a similar flat space extends from the anal to the under lobe of the caudal, and there is a 

 broader and somewhat triangular one between the ventrals and anal. The pectorals, rather 

 larger than the first dorsal, have, like it, nearly the form of a latteen sail, but the latter fin has 



2p 



