FISHES OF WEST COAST OF PEEU. 129 



Scales large, regular in arrangement; head without scales; a line 

 in front of dorsal along median line of back not crossed by the 

 scales; lateral line arched, following contour of back. 



Color in alcohol, olivaceous or yellow tinged with red; a large 

 black area under fourth dorsal spine, crossing lateral line, more 

 pronounced below line; black area confined to center of scales, mar- 

 gins lighter; two individuals with a distinct black notch at base 

 of caudal; a black area on opercle; fins body color; sides of head 

 with 4 or 5 wavy bands, these indistinct or absent in these indi- 

 viduals. 



Pacific coast of tropical America, Mazatlan to Peru. 



Family SCARIDAE. 



THE PAKROTFISHES. 



Genus XENOSCARUS, new genus. 



Type of genu^. — Xenoscarus denticulatus. Jaws subequal, the 

 lower barely included ; gill membranes narrowly joined to the isthmus, 

 across which they form a broad fold ; upper lip double for its entire 

 length; lateral line continuous; one row of scales on cheek; teeth 

 white, distinct, imbricated in regular oblique rows in both jaws, 

 wholly concealing the dental plates to the anterior edge of which they 

 are affixed ; cutting edge of each jaw formed by the outer teeth, the 

 dental plate not reaching the edge, and visible only from within; 

 dorsal spines IX, soft and flexible; base of dorsal and anal with 

 scaly sheath. 



This genus is related to Calotomus in the character of the teeth 

 and flexibility of dorsal spines, but differs from it in having the 

 upper lip double for its entire length, in this respect agreeing with 

 Sparisoma, and in having the gill membranes forming a broad fold 

 across the isthmus. From Scarichthys Bleeker, it differs in having 

 the teeth distinct. 



{^tvos, strange; aKapos, Scarus, the ancient name of Sparisoma 

 cretense). 



154. XENOSCARUS DENTICULATUS, new species. 



FOCOOHO SE UAB. 



Plate 12, fig. 1. 



Type.—C9.t. No. 77619, U.S.N.M., a specimen 25 cm. in length 

 field Xo. 09474), and paratype field No. 09500, 24.1 cm. in length, 

 from Lobos de Afeura. 



Head 3.16 in length; depth 3; eye 5.66 in hciajd; sno\it 2.5; inter- 

 orbital 3.4; pectoral 1.69; ventral 1.91; D. IX, 10; A. Ill, 9; scales 

 H-25-6 (5i). 



Interorbital broad, flat, raised but little above upper edge of 

 orbit; dorsal outline of head nearly straight; dorsal and ventral 



