HOMOPRION XANTHURUS. 171 



the nostrils are near together ; the posterior and slightly larger is oval in shape, 

 and very near the eye ; the anterior is round. 



The mouth is of moderate size, the upper jaw extending to the middle of the 

 orbit ; the lower is shorter than the upper jaw, and both are armed with two or 

 three series of small, pointed, recurved, card-like teeth, with an outer row of larger, 

 conical, pointed teeth, about fifteen in number ; the largest teeth of this row are 

 in front. The tongue is rather thick, narrow, and round in front. The pharyngeal 

 bones are armed with numerous villiform and pointed teeth. The pre-opercle is 

 slightly rounded at its angle, with its ascending border directed rather back- 

 ward and finely serrated above, but it has large and radiating serratures at its an- 

 gle. The opercle is emarginate behind, and terminates in two flat points, from 

 wliich a fleshy fold is extended. The inter-opercle is short, broad, and semi- 

 circular. The gill-openings are large ; there are seven branchial rays. 



There are two dorsal fins, contiguous, and of considerable elevation ; the ante- 

 rior begins behind the root of the pectoral, and has eleven spines partially received 

 in a groove ; the posterior has one spine and twenty-one soft rays, standing in a 

 groove, and partially covered near their roots with minute scales. The pectoral 

 begins near the opercle, is short, and has fourteen rays. The ventral is rather 

 large ; it arises behind the root of the pectoral, and extends beyond it, and has 

 one spinous and five soft rays. The anal is large, and begins on a line with the 

 middle of the posterior dorsal fin, and terminates with it behind ; it has two spines, 

 the first short, and the second long and very stout ; it has nine soft rays, the 

 three or four last very short. The caudal is full, entire, or slightly longest in 

 the middle, with minute scales on its membrane ; it has seventeen rays. 



The scales are nearly semicircular, straight before, with fifteen radiating striae, 

 slightly undulating in their course ; round and finely ciliated behind. The lateral 

 line is at first concurrent with the outline of the back, and runs about the superior 

 third of the body, to the middle of the soft dorsal, when it descends to the median 

 plane, and thus continues to the tip of the tail ; its scale is sub-quadrilateral, 

 rounded behind, where it is ciliated and very slightly emarginate. 



