26o 



BULLETIN OF THE BUREAU OF FISHERIES. 



This West Indian species is rare in the Beaiifort region, the first example being taken by Coles 

 in the bight of Cape Lookout in July, igii. In July, 1914, Coles took six additional specimens in the 

 eame locality. It may be expected at other points in the South Atlantic States. 



14. Carcharhinus commersonii Blainville. 



Carcharhinus mtlberti, Linton, 1905, p. 341 ; Smith, 1907, p. 34 (in part). 

 Carcharhinus latnia, Gudger, 1913b, p. 97; Coles, 1914. p. 90. 



27 — ^I 

 Teeth. — Teeth in ' rows; upper teeth erect, very broadly triangular, coarsely serrate; anterior 



margins straight to slightly convex, posterior margin straight to slightly concave ; tips of teeth near angles 

 slightly recurved, those at angles more or less distinctly notched; one or two rows of minute teeth at 



Fig. is- — Denticles, Carcharhinus commersonii, taken from back behind first dorsal, specimea 

 from Cape Lookout. N. C. 



symphysis; lower teeth smaller, erect, with relatively short cusps and broad bases, cusps very finely 

 serrate, broader than in related species; two or three rows of minute teeth at symphysis. 



The teeth of this species more closely resemble tliose of C. mtlberti than any other in this region. 

 The upper teeth are shorter and broader, the length of the side of a tooth is more nearly equal to its 

 breadth at base than in milberii, serrations coarser, posterior margins of lateral teeth straighter; lower jaw 

 with two or three rows of minute teeth at symphysis instead of one. 



Denticles. — The dermal denticles are large (about 0.32 mm. long by 0.42 mm. broad in a shark 2 m. 

 long), closely imbricated, heavy, five-keeled; keels prominent, parallel; apical margin smooth, scalloped 

 or with five distinct pointed lobes, depending upon position and wear they have been subjected to; 

 pedicel low, stout, resting on a large rhomboidal basal plate. 



The denticles represented in the drawing were taken from the back behind the first dorsal fin and 

 were the only ones available at the time. Denticles under the dorsal have much less prominent apical 

 lobes, more closely resembling apical margin of C. acronotus. 



