FISHES OF HAWAIIAN ISLANDS. 
43 
A large shark, abounding in all warm seas, common on the east coast of Japan. It was seen by 
Dr. Jordan at Misaki, Nagasaki, Tokyo, and Yokohama. No one has yet compared specimens of the 
Japanese fish with those from California or the Mediterranean, and the species may prove different. 
Squalus vulpes Graelin, Syst.-Nat., I, 1496, 1788, Mediterranean; after Pennant. 
Squalus vulpinus Bonnaterre, Tableau Encycl. Ichthy., 9, 1788, Mediterranean; after Pennant. 
Alopias macrourus Rafinesque, Caratteri di Alcuni Generi, 12, 1810, Sicily. 
Squalus alopecias Gronow, Cat. Pishes, 7, 1854, Mediterranean. 
Carckarias vulpes, De Kay, New York Fauna, IV, Fishes; 348, pi. LXI, fig. 199, 1842. 
Alopias vulpes, DumOril, Elasmobr., I, 421, 1865; Day, Fishes of India, Supplement, 810, 1888; Jordan & Gilbert, Synopsis. 
27, 1883; Jordan & Evermann, Fishes North and Mid. Amer., I, 45, 1896. 
Alopecias vulpes, Gunther, Cat. , VIII, 393, 1870. 
Family VI. FAMNID4L — The Mackerel Sharks. 
Sharks of large size, with the body stout, the mouth wide with large teeth, and the tail slender; 
the caudal fin lunate, the 2 lobes being not very unequal, the upper lobe strongly bent upward; 
caudal peduncle with a strong keel on each side; gill-openings wide, all in front of the pectoral, entirely 
lateral, not extending under the throat; first dorsal large; pectorals large; ventrals moderate; second 
dorsal and anal very small;, a pit. at the root of the caudal; spiracles minute or absent. Genera 3, 
species 6 or more, besides numerous fossil species. In this family the dentition, as well as the muscu- 
lar system, reaches its highest degree of specialization. 
a. Lamnix: Teeth slender and sharp, with entire, edges Isuropsis, p. — • 
aa. Car char odontmx: Teeth with serrated edges, compressed, and triangular in form, without basal cusp. . Car char odon, p. — 
Genus 9. ISUROPSIS Gill. 
Snout, rather long and pointed; the body formed much like that of a tunny or mackerel; iirst dor- 
sal large, inserted entirely behind pectorals, nearly midway between pectorals and ventrals; pectorals 
large; second dorsal and anal very small; caudal peduncle slender; teeth long, lanceolate, with sharp 
entire cutting edges and no basal cusps. 
Isuropsis Gill, Ann. Lyc. Nat. Hist. N. Y., VIII, 1861, 398 ( (jlaucus ). 
11. Isuropsis g-lauca (Muller & Henle). Fig. 5. 
Snout long, pointed; teeth in 4 rows, very long, fiexuous, without denticles at base; spiracles very 
small; first dorsal inserted well backward, midway between pectoral and ventral, scarcely longer than 
high, its upper angle rounded. 
Color, dark blue, white below. 
Coasts of Japan and southward, rather common about Nagasaki. Many jaws and a stuffed foetus 
are in possession of Mr. Yahiro at Nagasaki. A specimen 7 feet long was taken by Jordan and Snyder 
at Matsushima, of which the head. was preserved.* Many teeth and jaws of specimens from Honolulu 
are in possession of Mr. E. L. Berndt, of Honolulu. 
