1880.J NATURAL SCIENCES OF PHILADELPHIA. 15 



depth slightly less than four to rather more than fives times in the 

 total length ; head, 4j-4f in the same. Greatest thickness about 

 2^ in the greatest depth. Eye, 4-5 times ; snout, 3-3^ times in 

 the length of the head. Interorbital width, measured round the 

 curve of the forehead, 2|-2f in the same. Caudal peduncle, 3-4 

 times in the greatest depth. Distance from the spinous dorsal to 

 the lateral line, xg^-l^ times in the height of the last dorsal spine. 

 Nostrils conspicuous, on the horizon of the centre of the pupil, an- 

 terior with a valve posteriorly ; posterior larger, simple, subeircular, 

 distant from the eye about one-third of the diameter of tlie latter. 



Ej^es large, lateral, subeircular, their posterior margin nearer 

 the tip of the operculum than that of the snout. 



Mouth slightly ascending forwards ; tip of the intermaxillary 

 level with the lower margin of the orbit ; posterior extremity of 

 maxillary nearly vertical with the anterior orbital margin. Max- 

 illar\^ narrow throughout, its posterior portion free, but the 

 greater part of its upper edge concealed behind the large preorbital 

 in the closed mouth. Jaws equal in front in the closed mouth. 

 Teeth in jaws in several rows in front, diminishing to a single row 

 farther back on the sides, rather small, slender, acute, recurved at 

 tip, but those in front of the mandible in the outer row inclined 

 forwards. Teeth in front largest, those on the sides diminishing, 

 but the hindermost tooth on each side of each jaw more or less 

 developed as a canine, though still shorter than tlie anterior teeth. 



Xo teeth on vomer or palatines. Upper phaiyngeals set with 

 sharp, irregularly spaced, eardiform teeth; lower pharyngeals with 

 an outer and inner row of similar teeth, with some irregularly placed 

 teeth between the rows. Lower phaiyngeals entirely separate. 



(rill-rakers of front of first branchial arch slender, rather stiff, 

 ab6ut ^ the diameter of the eye, all the others tubercular. 



Hinder border of preoperculum vertical, very slightl}- curved, 

 lower angle rounded, set with teeth which slightly increase in 

 size at the angle, but do not extend along the lower border. 

 Operculum ending behind in a broad flat spine. 



Dorsal commencing above the upper pectoral axil, very long, 

 the tips of its terminal rays reaching the caudal accessories ; the 

 length of its base about half the total length of the fish ; spinous 

 dorsal 3f-4 times in the total length of the fin, and lower than the 

 soft portion. First dorsal spine shortest, the others increasing 

 rapidly to the fifth, more slowly to the eighth or ninth ; the longest 

 6^-8 times in the total length of the fin. 



