246 



BULLETIN OF THE BUREAU OF FISHERIES 



on Lookout Shoals, where they prove very troublesome to the bluefish fishermen, attacking the fish in 

 the nets, tearing the nets, and liberating the fish. The fishermen sometimes confuse tliis species with 

 another {Hypoprion brevirostris) , and some of the large examples reported to be the sand shark were 

 presumably the latter species. 



Family VULPECULID.€. The thresher sharks. 



Genus VULPECULA Valmont. 

 2. Vulpecula marina Valmont. 



Vulpecuta marina. RadcUffe, 1914, p. 414. 

 Alopias vulpes. Coles, 1914, p. 91. 



Teeth. — Teeth two-rooted, in 



42 /42Y 

 44 V37/ 



rows, small, compressed, subtriangular; cusps narrow, 



smooth-edged, sharp-pointed, slightly recurved at tip, anterior margin sinuate, posterior margin concave; 

 bases broad; a minute denticle present on one or both sides of many of the teeth, frequently absent on 

 functioning teeth; teeth in the third row in upper jaw and in the eighth row in the lower jaw smaller; 



a row of minute teeth on each side of 

 symphysis of lower jaw; teeth at angles 

 of mouth small; outer row and part of 

 the second fimctioning. 



Denticles. — ^The dermal denticles are 

 normally five-keeled, very small, being 

 about 0.21 by 0.21 mm. in an example 

 about 458.2 cm. long, thin, subequal, close- 

 set, closely overlapping; outer siuface flat- 

 tened; keels low, distinct, interspaces 

 not deeply grooved ; apical margin slightly 

 dentate; basal margin rounded; pedicel 

 small, slender, high; basal plate small, 

 rhomboidal. 



The first record of this species for the 

 coast of North Carolina is that of an exam- 

 ple found on the beach in the bight of Cape 

 Lookout April 24, 1913. This specimen 

 had evidently become entangled in the 

 V\o. 2.— Denticles, Vulpecula marina, about 458.2 cm. lone, from Cape nets of the fishermen; the elongate caudal 

 Lookout, N. C. jgl^g jjgjj been severed from tlie body and 



lost. The length of the body to the base of tlie caudal was about 22S.6 cm. (7 feet); estimated total 

 length, 457.2 cm. (15 feet). 



Head short, thick, very robust; snout short, subconical, its length less tlian tlie distance from its 

 tip to front of mouth; eye large, without nictitating membrane, horizontal diameter 1.25 in vertical 

 diameter, 2.66 in snout; nostrils large, interspace between nostrils about double length of aperture; 

 nasal flap acute-angled, apertiu-e divided; mouth small, its length nearly equal to its width; spiracle 

 small, behind middle of eye, its distance from eye 1.75 in horizontal diameter of eye, apertxxre one- 

 tenth horizontal diameter of ej'e. 



First dorsal large, as high as long, distal margin concave, lower lobe acute; origin of dorsal over 

 inner angle of pectoral; second dorsal very small, its distal margin straight, produced posteriorly in a 

 long, acuminate lobe; anal small, similar to second dorsal, situated nearer base of caudal than base 

 of ventrals; ventrals short, broad, breadth about equal to length, distal margin sinuous, rather deeply 

 concave mesially; claspers slender, pointed, very elongate, nearlj' four times length of inner lobe of 

 ventrals, their tips extending beyond origin of anal; pectorals narrow, falcate. 



Color of back and sides bluish slate, sides of head below spiracle lighter; region aroimd mouth, 

 thence backward on ventral siu^ace, white; from axil of pectoral to behind base of first dorsal the 

 white coloration of belly extends well up on the sides of die bod)- ; behind the ventrals the white color- 

 ation again encroaches on the sides of the body. 



Coles reports observing one of these sharks feeding in the bight of Cape Lookout late in July, I9i4' 



11 Carman, The Plagiostomia, p. 31. 



