PROCEEDINGS OF UNITED STATES NATIONAL MUSEUM. 259 



its height at the middle of the caudal peduncle one twenty-ninth of the 

 same- 

 Scales arranged in about 115 vertical rows and about 38 horizontal 

 ones, about 11 being between the origin of the dorsal and the lateral 

 line and about 27 below the lateral line. Lateral line slightly curved 

 upward in the anterior fourth of its length. 



Length of head contained more than four and one-quarter times in 

 that of the body ; its width half its length and less than double that of 

 interorbital area. 



The barbel is short, its length being scarcely equal to half the diame- 

 ter of the orbit and about one-tenth the length of the head. The width 

 of interorbital area is about equal to the longitudinal diameter of the 

 orbit, in the larger specimen slightly greater. The diameter of the orbit 

 is equal to or slightly greater than one-fourth the length of the head. 

 The length of the snout is equal to that of the oi)erculum and less than 

 width of interorbital area. 



The maxillary extends to vertical from posterior margin of the orbit, 

 its length about equal to the greatest width of the head. Mandible 

 equals one-eighth of total length without caudal. 



Snout equal to operculum in length, obtusely pointed, much de- 

 pressed, its lateral outline subcouical, a conspicuous keel extending 

 backward along the lower line of the orbit to its posterior margin. 

 The head and mouth closely resemble those of some species of Macru- 

 rus, except that the keel is covered with small, smooth scales and is not 

 overhanging. Lips scaleless. 



Teeth in the jaws imperfectly serial, villiform, recurved; a small ob- 

 long patch of similar teeth on the head of the vomer; none on the 

 palatine^*. 



First dorsal fin inserted at a distance from the snout somewhat greater 

 than twice the height of the body at the ventrals ; its first ray is much 

 prolonged, its length greater than that of the head, and nearly as long 

 or longer (in the larger specimen) than the distance from the snout to 

 the beginning of the dorsal. The second ray is contained less than four 

 times, the third six times or less in the first, the fourth about ten times. 

 The length of the base of second dorsal is somewhat more than twice 

 the distance of its insertion from the snout ; its greatest height, which 

 is in the posterior fourth of its length (near the 40th ray), is contained 

 about six or seven times in the length of its base. 



The vent is situated at a point equidistant from snout and tip of cau- 

 dal, under the 19th ray of second dorsal fin. The anal fin is inserted at 

 a distance behind it equal to length of second anal ray. Its length of 

 base is slightly more than half that of second dorsal. It has a consider- 

 able depression in its middle outline. The last rays of dorsal and anal 

 are of equal length, and are directly opposite each other. 



The caudal vseems to be somewhat rounded. The length of the middle 

 rays contained more than nine times in total length without caudal, and 

 more than ten times in length including caudal. 



