FISHES OF THE GULF OF MAINE 25 



THE SMOOTH DOGFISHES. FAMILY GALEORHINID^ 



These are rather small sharks (17 known species) with two dorsal fins, the 

 first large and the second usually much smaller, without spines. The upper lobe 

 of the tail is much longer than the lower, anal fins are present, and the teeth are flat 

 and pavementhke. Except for the teeth they closely resemble the requiem sharks 

 (family Carcharinidse, p. 27). 



4. Smooth dogfish {Galeorhinus Isevis Vaimont) 



Grayfish; Smooth dog; Smooth hound; Switch-tail; Whtpper-tail 



Jordan and Evermann (Mustelus canis Mitchill), 1896-1900, p. 29. 

 Garman, 1913, p. 176. 



Description. — The smooth dog is easily identified by the presence of two 

 large spineless dorsal fins, the first larger than the second, combined with an anal 

 as well as the paired ventral fins on the lower surface; a tail of typical shark outline — 

 that is, the upper lobe longer than the lower but not excessively elongated — and 

 with flat granular teeth. So different, indeed, are the teeth from the cutting teeth 



Fio. 5.— Smooth dogfish (Galeorhinus Isem) 



of all our other sharks, that a glance at the mouth is enough to separate this species 

 from the young of any larger Gulf of Maine shark. In form this httle shark is 

 slender, flattened below, with tapering but blunt snout. Its first dorsal originates 

 nearly over the hind angle of the pectorals and is decidedly larger than the second. 

 The latter, in turn, is about twice as large as the anal, over which it stands. The 

 hind margin of the upper lobe of the caudal is deeply notched near the tip ; the lower 

 caudal lobe is very small. 



Size. — ^Adult smooth dogs average about 2 to 3 feet in length, but they have 

 been taken up to 5 feet in length. 



Color. — Light gray above ; paler gray below. 



General range. — Cape Cod to Cuba in American waters; also off the coasts of 

 southern Europe. 



Occurrence in the Gulf of Maine. — The smooth dog is extremely abundant 

 west and south of Cape Cod. In Long Island waters, for example, it is one of 

 the commonest and most generally distributed of fishes from June until November, 

 and it aboimds equally throughout the summer and early autumn in the Woods 

 Hole region on all kinds of bottom. This, however, is the most easterly outpost 

 for its presence in any numbers, for though it has been reported from Provincetown, 



