TSURIDAE, 31 



Alopias vulpes Bonaparte, 1841, Icon. Fauna Ital., Posci; Muller & Henle, 1841, Plagios., p. 74, pi. 35, 

 f. 1 (teeth); Kroyer, 1853, Danm. fiske, 3, p. 929, 937; Dum^ril, 1865, Elasm., p. 421; Boca«e 

 & Capello, 1866, Plagios., p. 14; Doderlein, 1881, Man. ittiol. Medit., 2, p. 52; Moreau, 1881, 

 Poiss. France, 1, p. 287; Jordan & Gilbert, 1883, Bull. 16, U. S. nat. mu.s., p. 27; Day, 1884, Brit, 

 fishes, 2, p. 300, pi. 157; 1888, Ind. fishes, Suppl., p. 810; Garman, 1888, Bull. M. C. Z., 17, p. 80, 

 pi. 12-13; JoRD. & EvERM., 1896, Bull. 47, U. S. nat. mus., p. 45; 1900, ibid., Atlas, pi. 6, fig. 20. 



Squalus alopecias Gray, 1854, Gron. syst., p. 7. 



Trunk robust, less than half of the total length, little deeper than wide from 

 the nape to the dorsal. Head short, less than one seventh of the total, forehead 

 steep. Snout broader than deep, bluntly rounded at the end. Nostrils small, 

 transverse, nearer to the mouth than to the end of the snout, nearly midway 

 from the eyes; anterior valve with a short lobe near the inner edge. Mouth 

 medium, semicircular; outer labial fold half as long as the mouth, inner half as 

 long as the outer. Teeth small, with a sharp smooth-edged cusp and a broader 

 base, in f? rows, in a specimen of four feet four inches in length, the third tooth, 

 from the median if present, on the upper jaws little smaller. Eye large, 

 diameter nearly half the length of the snout. Spiracle minute, behind the eye 

 one diameter of the orbit. Gill openings moderate, hindmost two of each side 

 close together at their lower angles and above the pectorals. Front margin of 

 pectorals about one and two thirds times the length of both inner margin and 

 base. Dorsal large, in height equal its entire length, origin above the inner 

 angle of the pectoral, not reaching a vertical from the ventrals. Second dorsal 

 and anal equal, small, origin of latter about one length of its base behind the 

 base of the former. Fins all concave on the hind border. Caudal peduncle 

 strong, deeper than wide; fin more than half of the total length, with a strong 

 subcaudal lobe and with a shallow notch separating the subcaudal from the 

 terminal fin. 



Total length 52, snout to abdominal pores 18, snout to caudal 2H, snout 

 to fifth gill opening 7, snout to mouth H, and caudal fin 30^ inches. 



Dark plumbeous brown on back and flanks to the level of the spiracle where 

 there is a rather abrupt change to the white of the lower surfaces; lower sides of 

 pectorals and a space below the gill openings dark. 



Specimen described and figured from Massachusetts Bay. 



ISURIDAE. 



Body fusiform; head subcorneal; caudal peduncle depressed, with lateral 

 folds and caudal pits; vertebral axis of caudal much raised backward from the 

 horizontal. Nostrils oblique, near the mouth but not confluent with it. Mouth 

 large, crescent-shaped, with labial folds. Eyes without nictitating folds. 



