FISHES OF WEST COAST OF PERU. 7 



Bod}'' rather strongly arched, caudal peduncle slender; head 

 broad, depressed; snout rounded; spiracle large, 3 in eye; margins 

 of each side of mouth slightly concave; teeth blunt, paved, without 

 cusps, differing greatly in appearance from those of the types of Mus- 

 telus dorsalis, which have a well-developed cusp on each tooth; 

 labial folds well develoj^ed, the outer 1.8 in the distance from its tip 

 to symphysis of lower jaw. 



First dorsal high, distal margin slightly concave, tip of posterior 

 lobe reaching vertical from base of ventral; second dorsal smaller 

 but similar in shape to the first dorsal; upper caudal lobe 5.12 in 

 total length ; lower lobe slightly concave, anal similar to second dor- 

 sal in shape but much smaller, inserted under middle of second dor- 

 sal ; i^ectoral large, distal margin straight ; ventrals with their inner 

 margin lengthened, longer than outer margin, tips reaching more 

 than half distance to base of anal. 



Color in alcohol, olivaceous, tinged with yellowish on ventral sur- 

 face ; dorsal surface flecked with white. 



Coloration of field No. 69107 similar to the tyx)e. 



Color of small male from Lobos de Tierra, silvery plumbeous on 

 back and sides, ventral surface paler ; back crossed by about 15 black 

 or dusky crossbands, these reaching lateral line; six of these cross- 

 bands in front of the dorsal. 



This species has the general form of Mustehu dorsalis (the types 

 of which we have examined), differing in having the body and head 

 deeper, and the snout less pointed in individuals of the same size; 

 the loAver caudal lobe anterior to the notch, shorter, 7.52 to 7.75 in 

 the total length (6,62 to 6.68 in types of M. dorsalis) and in the well- 

 marked differences in the character of the teeth and coloration. The 

 description of individuals from Callao identified by Abbott as G. 

 dorsalis agrees in all essential characters with these specimens. 



Named for James Francis Abbott in recognition of his valuable 

 contributions to our knowledge of the ichthyology of Peru. 



6. MUSTELUS DORSALIS Gill. 



Plate 1, fig. 3; plate 2, fig. 1. 

 TOLLO. 



Mustelus dorsalis Gill, Proe. Acad. Nat. Sci. PMla., 1864, p. 149 ; Panama. 

 Galeus dorsalis Jordan and Evermann, Fishes North and Mid. Amer., 



1896, vol. 1, p. 30. — Gilbert and Stakks, Fishes of Panama Bay, Mem. 



Cal. Acad. Sci., vol. 4, 1904, p. 7, pi. 1, fig. 2, 2a. (Not of Abbott.) 



One specimen, a male, field No. 09435, 50 cm. in length, from 

 Pacasmayo. 



