FISHES OF WEST COAST OF PERU. 15 



of disk; another narrow band of closer set, slightly stronger prickles 

 around spiracle behind eyes; concave interorbital space with scat- 

 tered prickles ; a narrow patch beginning opposite the first branchial 

 aperture and extending along the border of the disk to the tip of 

 snout; in all the patches the prickles are recurved so that they feel 

 smooth if the finger is passed backward; a short stout spine before 

 and another behind eye on interorbital ridge ; a short row of similar 

 spines on median line of back behind spiracle ; a patch of similar 

 spines in center of posterior projecting lobe of pectoral; a row of 

 10 stout triangular spines on median line of tail in front of dorsal; 

 a single stout spine between dorsals and a row of prickles on median 

 line of back ; a continuation of spines on tail. 



Disk opposite eyes, convex, then becoming slightly concave; pos- 

 •terior border rounded ; pectoral rays about TO. 



Color, in alcohol, back brownish, becoming olive-gray on the 

 margins of the disk ; ventral surface grayish white. 



In the male the prickles are stronger; on the median line of the 

 back anteriorly there is a single enlarged spine surrounded by an 

 elongate patch of prickles; there are 12 stout spines on median line 

 of tail in front of dorsal, 1 between dorsals; in front of spines on 

 tail there is a patch of prickles extending along median line of 

 back; no group of spines on posterior lobe of pectoral; opposite 

 broadest part of disk and nearly parallel with it near the margin 

 there is a double row of stout recurved spines, 16 spines in each 

 row ; on the right side there are several spines forming a third row ; 

 pectoral rays about 70. 



Color in alcohol, back brown, with olive spots about size of eyes 

 tending to form rows parallel with median line of back; the brown 

 fading out to olive-gray on borders of disk; ventral surface grayish- 

 white. 



The more pointed snout, the stout spines near pectoral border, and 

 absence of group on posterior lobe, the difference in coloration, and 

 the elongate claspers reaching beyond origin of first dorsal serve to 

 distinguish the two. A greater difference lies in the remarkable char- 

 acter of the teeth. In the female they are pavementlike, with only 

 a very slight raised area in center of tooth ; in the male they are 

 strong, recurved, conical teeth, and the mouth is more arched. Doctor 

 Steindachner does not indicate a spine between dorsals and no patch 

 of spines on posterior lobe of pectoral; in other respects our ex- 

 amples agree with the specimen described and figured by him. 

 Delfin's statement in his description of R. hurgeri that there are 

 about 52 pectoral rays is undoubtedly a mistake, for if the short 

 anterior rays are counted, there are about 70 rays. 



