312 PBISTIPOMATlDiE. 



9. Hsemulon xanthopterum. 



Haeiuuloii bonariense, Cuv. "^ J'a/. \ . p. l^'U. 



xanthopterum, Cuv. Sr Val. v. p. 2-"}4. 



heterodon, Cuv. ^- Val. v. p. 2^^). pi. 121. 



D. 11 I ^^. A. |. L. lat. 50. Vert. 11/15. 



The height of the body is 3 or 3^ in the total length, the length 

 of the head 3| or 3|. The snout rather pointed, of moderate length, 

 rather longer than the diameter of the eye, which is 3| in the length 

 of the head. The upper maxillary does not fuUy extend to the 

 vertical from the centre of the orbit. The posterior limb of the 

 prcDoperculum is slightly emarginate and minutely denticulated ; the 

 angle Avith rather stronger spinous teeth. The dorsal fin is notched ; 

 the spines are moderately strong ; the fourth the longest, exactly 

 one-half the length of the head. The soft dorsal, the caudal, and 

 anal fins are thickly enveloped by scales. Caudalis forked ; the 

 second anal spine is stronger and longer than the third, and rather 

 longer than the longest of the dorsal. The pectoral fins are tm-ned 

 upwards. Tlie lateral scales hettveen the pectoral Jin and the lateral 

 line are conspicuouslij much larger than the remainder. Coloration 

 uniform, with oblique bands beneath the lateral line ; a deep-black 

 spot is concealed by the angle of the praeoperculum. 



Atlantic coasts of Tropical America. 



a, b. Adult. West Indies. 



c. Adult : skeleton. West Indies. 



d. Fine specimen. From the Haslar Collection. 



e-l. Adult : stuffed. West Indies. Purchased of Mr. Scrivener. 



m. Adult : stuffed. Martinique. 



n-y. Adult and half-grown : skins. Jamaica. From Dr. Pamell's 



Collection. 

 z. Half-grown : skin. Trinidad. Presented by J. B. Richardson, 



Esq. 

 a. Half-grown. Puerto CiibeUo. Purchased of Mr. Brandt. 

 /5. Half-grown. Old Collection, as Perca chromis. 

 y. Half-grown : stuffed. From Mr. YarreU's Collection. 



Peritoneum black. 



Skeleton. — The system of muciferous channels is more developed 

 than in Fristipoma, but much less than in the true Sci(jemdoe. There 

 are four very distinct openings on the upper part of the skull, between 

 the eyes ; the posterior and smaller pair close together ; the anterior 

 more distant from each other, and close behind the turbinal bone, 

 which, more strongly developed than usual, forms a soHd half- 

 channel. Between these openings there is a deep longitudinal 

 groove, wddening between the turbinal bones to receive the processes 

 of the intermaxillaries. The occipital crest is very prominent, the 

 horizontal portion being wider than the vertical, and extending on the 

 frontal bones ; the latci'al crests are relatively less developed, but very 

 distinct, and the outer one is transformed into a muciferous channel, 

 commencing with an elongate opening above the posterior pait of 



