2 BULLETIN 95, UNITED STATES NATIONAL MUSEUM. 



The common species names given are local or vernacular names 

 supplied by Doctor Coker. / 



The writers take this opportunity to express their appreciation 

 of aid rendered and courtesies extended to them by the Hon. Eduardo 

 Higginson, Peruvian consul general at New York, and to Dr. Robert 

 E. Coker, director of the Fairport (Iowa) Biological Laboratory of 

 the Bureau of Fisheries. 



Acknowledgement should be made to Senor Don Carlos Larrabure 

 y Correa, director of public works for the Peruvian Government, 

 whose breadth of interest and effective energy have made possible the 

 study and report on the collections in the present form. 



DESCRIPTION OF SPECIES. 



Family HETERODONTIDAE. 



THE BULLHEAD SHARKS. 



Not until now has any species of this family been reported from 

 Peruvian waters. Doctor Coker's collections contains a single speci- 

 men which does not belong to an}^ previously described species. 



Genus GYROPLEURODUS Gill. 



1. GYROPLEURODUS PERUANUS, new species. 



GATOj sirfJo. 



Plate 1, fig. 1. 



A single specimen, the type. Cat. No. 77691, U. S. Nat. Mus. (field 

 No. 09509), 56.5 cm. in length, from Lobos de Tierra. 



Length of head to branchial region, 5.25 in total length; depth 

 5.6; eye 6.75 in head; interocular 2.07; snout 1.9; length of first 

 gill opening 3.66 ; length of fifth gill opening one-half that of first. 

 Body robust anteriorly, tapering posteriorly; caudal peduncle 

 slender, its depth about one-fifth length of head; head short and 

 stout, nearly as broad as long ; snout blunt, ridges from tip of snout 

 converging for half the distance to eyes, thence diverging and merg- 

 ing into the strong supraorbital ridges, the latter terminating just 

 behind the eyes; interorbital concave. Teeth in front of jaws 

 tricuspid, the middle cusps strongest, arranged in about six con- 

 verging rows; behind these on the sides of the jaws there are five 

 oblique rows of elongate, carinate teeth, each cross series composed 

 of five teeth, the whole patch rhomboidal in outline; eyes small, in 

 a groove between the overhanging supraorbital ridge and the tumid 

 cheek. Origin of first dorsal posterior in its insertion to the verti- 

 cal from posterior base of pectoral; distance from tip of snout to 

 its insertion 2.75 in total length of body ; distal portion rounded and 

 not lunate as in G. galeatus^ its height 2.62 in length of head ; length 

 of base, 2.2; first dorsal spine very stout and blunt, its height one- 



