424 PROCEEDINGS OF UNITED STATES NATIONAL MUSEUM. 



the maxillary a distance equal to the least height of the tail. Teeth 

 brush-like, iu bauds; the baud of the upper jaw more developed than 

 that of the lower oue, the leugth of the baud equaliug half that of the eye. 

 The maxillary extends to the perpendicular through the anterior margin 

 of the pupil; the mandible, to the vertical through the posterior margin 

 of the eye. The leugth of the mandible equals half that of the head. 

 The preoperculum is denticulated on its lower border and at the angle, 

 the denticulations at the angle being slightly the largest. The gdl- 

 rakers are short, 12 iu number ou the anterior arch below the angle, the 

 longest one- fifth as long as the eye. The eye equals the snout iu length, 

 and is contained 3§ to 4 times in the length of the head. The naked 

 space above the premaxillary groove in the majority of the types is 

 prolonged backwards to an acute point, but in two of the types the 

 acute point is replaced by a scaly space. 



The distance of the spinous dorsal from the snout equals about IJ 

 times the length of the head. It is inserted nearly over the middle of 

 the pectoral base. The position of this fin varies very slightly in differ- 

 ent individuals. The subsequent spines to the seventh are much stouter 

 aud longer than any of the others, and are so graduated iu length that, 

 when the fin is erect, the outline of the anterior portion i)resents nearly 

 the figure of an isosceles triangle. The last two spines are nearly equal 

 iu leugth. The length of the first ray of tlie soft dorsal is nearly double 

 that of the last dorsal spine; the last ray being about as long as the 

 first. The spines aud rays all protrude from one-half to one-third of 

 their length beyond the membrane, giving to the fin a ragged appear- 

 ance. The basal sheath of the dorsal fin is thick and prominent. 



The insertion of the anal is equidistant between the tip of the snout 

 and the tip of the upper caudal lobe, the fin being inserted under the 

 perpendicular from the fourth dorsal ray. The first anal spine is short 

 and stout, being half as long as the diameter of the eye; the second 

 very stout, uot quite so long as the third, being equal in length to the 

 distance from the center of the eye to the end of the operculum. The 

 first ray of the anal is also elongate, giving to this fin, when expanded, 

 the appearance of an isosceles triangle, with base somewhat slenderer 

 than that described in the first dorsal. The soft anal in its posterior 

 part is lower than the soft dorsal. 



The caudal fin is deeply forked, the longest ray of the upper lobe be- 

 ing equal to about one-third of the body length, and five times as long 

 as the inner rays. 



The pectoral is inserted at the tip of the opercular flap, and has its 

 upper rays elongate, equalling the head in length. 



The ventral is inserted beneath the axil of the pectoral at a distance 

 from the snout equal to two-fifths of the length of the body. Its spine 

 is as long as the fourth spiue of the dorsal, but double as stout, the first 

 ray being j)rolonged. 



