436 REPORT OF COMMISSIONER OF FISH AND FISHERIES. 
between which they are intercalated. Medial part of branchiostegal membrane and 
the gular region covered with roundish plates, the whole forming a halbert-shaped — 
patch. Lateral line running on a series of small plates occupying the middle of the 
lateral face. Anteriorly these entirely disappear, the lateral line ascending and — 
running on the upper lateral series. About five large plates, sometimes bearing 
spines, lie behind upper axil of pectorals, between this ascending portion of the 
lateral line and the inferior lateral series of plates. 
Head depressed, tapering rapidly to the snout; depth of head at occiput two- 
thirds its width at preopercular spine, the latter contained 6} times in length of © 
body. Eye large, the orbit about equaling length of snout behind the serrated 
rostral ridge, 34 to 33 in head. Snout somewhat variable in length, averaging one- 
third head. Supraocular ridges strong, rugose, ending in a short, strong spine. An 
inner pair of ridges occupies the floor of the interorbital groove, very broad and 
closely joined anteriorly. The triangular space included between these latter ridges 
is flat and opens posteriorly onto the depressed occipital area. Occipital ridges low, ~ 
rounded, ending in very strong spines which form the first of the dorsal series; two 
or three small, rounded projections may occur on anterior ridges of occipital spines. 
The top and sides of head are more or less closely beset with very fine prickles, — 
which are most thickly clustered on occiput, interorbital area, upper part of opercles, 
suborbital chain, and sides of snout. A row of prickles on eyeball, just above pupil. 
Temporal ridge uneven, sometimes interrupted with a long, strong posterior spine. 
A strong spine, sometimes with an accessory tubercle, on middle of cheeks. Pre- 
orbital with two pairs of spines placed vertically, the upper ones directed outward — 
and upward, the lower spines directed downward and backward. Rostral ridges — 
rough, usually terminating posteriorly in a pair of spinous projections, which are — 
located midway between tip of snout and front of pupil. Anteriorly, at tip of snout, — 
these ridges expand to form such a vertically projecting, rounded, spinous lobe, the 
posterior spine of which is much the strongest and points backward and outward. 
In the very young the last-mentioned spines alone are present on snout, and are — 
directed very obliquely backward. Anteriorly ridges converge from them to tip of — 
snout and are very minutely serrulate. These ridges afterward increase in height 
and in strength of serrations, and become the spinous lobes already described. 
Two strong diverging spines at angle of preopercle and two rounded lobes below 
them. Three large plates and a number of smaller ones occupy cheeks below sub- 
orbital stay. Posterior portion of mandible expanded into a rough, projecting, bony 
prominence. 
Mouth horizontal, overpassed by the snout in adults for a distance equaling half 
or less than half diameter of orbit; the snout not noticeably projecting in the very — 
young. Maxillary reaching slightly beyond front of orbit, equaling half length of 
snout and eye. Teeth in broad bands in jaws; a distinct patch on front of vomer; 
none on palatines. Branchiostegal membranes broadly joined with a very narrow 
free fold posteriorly or with none. 
Six pairs of barbels on under side of head: One on under side of snout in front of 
premaxillaries; two at end of maxillary ; one near middle of maxillary; one on lower 
lip just below angle of mouth; one forked for half its length, at middle of side of 
lower lip. In their distribution, relative lengths, and in the constantly bifid char- 
acter of the last described, they correspond exactly with the barbels of L. decagonus, 
but the latter has apparently none on under side of snout. 
Interspace between dorsals somewhat variable, three-fourths to seven-eighths 
diameter of orbit. The anal begins two plates in advance of second dorsal. Pec- 
torals 54 in length of body, the lower rays graduated, four to six of the lower ones 
thickened, with exserted tips. Ventral fins nearly twice as long in males as in 
females, in the latter less than diameter of orbit. Cauda] slender, 1} in head. 
Head 44 to 44 in length. Dorsal v1 to vi-7 or 8; anal 6 or 7; pectoral 15; ventral 
1, 2; caudal with 11 rays and a rudiment of a twelfth below. Lateral line 40. 
