32 FISHES OF NORTH CAROLINA. 



Family GALEID.E. The Requiem Sharks. 



Ovo viviparous sharks, with the first dorsal fin short and high, entirely in 

 advance of ventrals; the second dorsal small and opposite anal; gill-openings of 

 moderate size; the last slit above base of pectorals; spiracles small or obsolete; no 

 keel on side of caudal peduncle; nictitating membrane present; no dorsal spines. 

 A very large family, found in all seas, with numerous genera, of which the follow- 

 ing are represented in South Atlantic fauna and several others may be looked 

 for*: 



I. Teeth blunt, flat, paved, without cusps or ridges; spiracles present; embryos not attached 



by a placenta Mustelus. 



ii. Teeth compressed, with entire or serrate edges; spiracles obsolete; embryos attached by a 

 placenta. 

 a. Angle of mouth without a groove which extends along either jaw; all teeth more or less 



serrate; first dorsal nearer to pectorals than to ventrals Carch.^rhinus. 



aa. Angle of mouth with a groove which extends along either jaw; teeth entire; first dorsal 

 midway between pectorals and ventrals Scoliodon. 



Genus MUSTELUS Cuvier. Dog-fishes. 



Small sharks, usually swimming in droves; body elongate, slender; mouth 

 small, crescent-shaped, with conspicuous labial folds; snout long and flat; teeth 

 small, many-rowed, pavement-like, those in two jaws similar; eye large, oval; 

 spiracles small; pectorals large; caudal nearly straight, the basal lobe very small. 

 Two American species, one on Pacific coast of ^lexico, and one on Alantic coasts 

 of America and Europe. {Mustelus, weasel or marten.) 



5. MUSTELUS CANIS (Mitchill). 

 ''Dog-fish"; Smooth Dog-fish. 



S(iuahis' canis Mitchill, Transactions of Literary and Philosophical Society of New York, i, 486, 1815; New- 

 York. 

 Mustelus Icevis, Goode, History of the .^merioan Menhaden, 41, 1879; Cape Hatteras. 

 Mustelus canis, Jordan & Evermann, 1896, 29. 



Diagnosis. — Body cylindrical, slender, peduncle long; head .25 total length without 

 caudal, twice greatest depth of body; snout .33 length of head; eye .4 length of snout; teeth in 

 about 10 rows in each jaw; caudal fin as long as head, its lower lobe .33 length of u]iper. Color: 

 uniform ashy gray, sometimes with pale spots; beneath white, {canis, dog.) 



The dog-fish is one of the most abundant of the sharks on the Atlantic coast 

 of the United States. Its maximum length is 5 feet and the average 2.5 to 3 feet. 

 It feeds largely on crabs, lobsters, and other bottom invertebrates. The flesh is 

 very palatable, and in Bermuda is highly esteemed, but in the United States the 

 fish has no economic value at present, but, on the contrary, is very destructive 

 in the New England fisheries, chiefly because it eats the food fish that have been 

 caught with lines and gill nets. 



The dog-fish is abundant at times off the North Carolina coast, and is often 

 caught in the beach seines in winter, although it usually keeps offshore. It is 



* Other sharks of this family that may eventually be recorded from North Carolina are: (1) The leopard, 

 tiger or spotted shark {Galeocerdo tigrinus), not uncommon on the east coast as far north as Massachusetts; a 

 large species, attaining a length of .30 feet, (2') The great blue shark {Prionace glaitca), rare on the .Atlantic 

 coast (two Mas.sachusetts records). (3) The tiburon {Aprionodon isodon), known from New York, Virginia 

 and Cuba. 



