THE HOENBD DOGFISH. 673 



and are occasioually taken in nets. They are of no special value, and cause much annoyance to 

 the fishermen. An individual taken at Wood's Holl, Massachusetts, in July, 1875, measured nine 

 feet seven inches, and weighed three hundred and eighty pounds, the liver weighing thirty-eight 

 pounds. It had in its stomach a blueflsh of five pounds' weight. These two species feed upon 

 moUusks as well as upon fish. Individuals examined by the Pish Commission were found to 

 contain bluefish, flounders, crabs, lobsters, and quantities of a small species of a bivalve shell, 

 Toldia sapotilla. 



The Blaok-finned Shark — Isog-omphodon maoulipinnis. 



This species resembles in shape the Blue Shark, from which it may be distinguished by its 

 hghter color and the presence of a prominent black spot upon the tip of each fin. The species is 

 found in the tropical parts of the Atlantic and Indian Oceans and on the Pacific coast of Central 

 America. It was first discovered on our coast in 1875, when several specimens were taken at 

 Wood's Holl, Massachusetts. 



The Tiger Shark — Galeocerdo tigrinus. 



This is a species which is found throughout the Atlantic and Indian Oceans and on the coast 

 of Japan. It was first noticed in our waters by Captain Atwood, who obtained specimens at 

 Provincetown, and has since been observed occasionally. It is one of the most active and grace- 

 ful of Sharks, as well as one of the most ferocious. Its teeth are like razors. In the stomach of 

 a specimen taken by Captain Atwood at Provincetown, nearly a whole full-grown sword-fish was 

 found ; ten or twelve wounds in the skin of the Shark gave evidence of the contest that must 

 have occurred. It feeds upon mollusks as well as upon other fishes. A specimen caught at 

 Wood's Holl in 1871 contained large univalve shells, Biiceinum undatum, and the sea-snail, Lunatia 

 heros. 



The Smooth or Blue Dogfish — Mustelus oanis. 



.The Smooth Dogfish of our waters, Mustelus canis, is without doubt specifically identical with 

 one of the common European species, M. vulgaris. The American name has, however, the right 

 of priority. Hitherto, only a single species has been recognized upon Atlantic coasts. It is quite 

 abundant on the coast of Southern i^ew England. It feeds upon crabs, lobsters, and other bottom- 

 loving invertebrates, its smooth pavement-like teeth being adapted for crushing the thick shells 

 of these animals rather than for seizing and holding active fishes. 



In Bermuda this fish is known as the "Nurse Shark," and is highly esteemed by the negroes 

 as food, and is also au important bait in the local fisheries. At Folkstone, England, they are 

 dried, and go by the name of " Folkstone beef." 



The Horned or Spiny Dogfish— Squalus aoanthias. 



This species is found in the North Atlantic, occurring on the coast of Europe from the North 

 Cape to the Mediterranean, and in our own waters south to New York. On the west coast it 

 ranges south to Santa Barbara. Little attention has been paid to its habits. I cannot do better 

 than quote fully the observations of Captain Atwood, who writes : 



" This Shark is the most common one upon our coast. I have seen it at Gay Head, Martha's 

 Vineyard, but know nothing further about its southerly limits. Both above and below Cape Cod 

 it is abundant, and is found all along the coast of Massachusetts, Maine, Nova Scotia, and the 

 Gulf of Saint Lawrence. I myself have ne^"er seen them farther north than the Magdalen 

 Islands and the east coast of Cape Breton Island, but reliable accounts say that it is found on the 

 southern coast of Newfoundland. As the Dogfish appear at Provincetown a little while after the 

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