34 BULLETIN 189, UNITED STATES NATIONAL MUSEUM 



Figure 6. — Mustelus dorsalis Gill. From a specimen 500 mm. long from Pacasmayo, Peru 

 (U.S.N.M. No. 77697). Insert, ventral view of head. (After Evermann and Radcliffc, 

 1S47.) 



Figure 7. — Mustelus maculatus (Kner and Steindachner). From the type of M. nigro- 

 maculatus Evermann and Radcliffe, 510 mm. long, Lobos de Tierra Island, Peru (U.S.N.M. 

 No. 77699). Insert, ventral view of head. (After Evermann and Radcliffe, 1917.) 



MUSTELUS MACULATUS (Kner and Steindachner) 



Caz6n; Tollo; Tollito 

 Figure 7 



Triakis maculatus Kner and Steindachner, 1866, p. 391, listed from the indefi- 

 nite locality "Sudsee" (original description).— Steindachner, 1869b, p. 26, 

 Mazatldn, Mexico. — Garman, 1913, p. 167 (redescribed from specimens 

 from Callao, Peru). — Bigelow and Schroeder, 1940, p. 428, pis. 17 and 

 19 (teeth and dermal denticles figured). — Fowler, 1941a, p. 223 (references, 

 range).— Beebe and Tee- Van, 1941, p. 101 (references, discussion). 



Mustelus nigromaculatus Evermann and Radcliffe, 1917, p. 9, pi. 2, fig. 2, 

 Lobos de Tierra, Peru (original description). 



Body rather robust anteriorly, becoming very slender posteriorly; 

 depth at origin of first dorsal 5.6 to 7.6 in length anterior to base of 

 upper lobe of caudal; caudal peduncle about two-thirds as wide as 



