PERISTEDIUM CRUSTOSUM. 113 



hy a considerable space below the symphysis ; lateral barbel witli about 

 eight groups of barblets, extending backward of tlie eye to the pectorals 

 or to the end of the suborbital keel. Eye large, prominent, half as loii"- 

 as the snout, one third of the length of the head, one and one 

 tliird times the interorbital widtli. Interorbital space arched longitudi- 

 nall}-, deeply concave transversely with strong ridges at the sides. Gill- 

 rakers slender, sharp, three to five plus twenty-four, several rudimentary, 

 longest one third as long as the orbit. Surfaces of the head harsh with 

 fine granulations. Above the forward part of the eye on tlie ridge there 

 is a group of two or more small sharp compressed hooked spines ; behind 

 the orbit the ridge rises in a stronger spine, and behind the latter a lower 

 one, behind which there is another still lower. At each side of the occiput 

 there is a strongly compressed spine, at the end of the ridge, bearing one to 

 two cusps. On tlie top of the basal half of each rostral process there is an 

 erect spine, and behind and inward from the nostrils there is a pair of 

 similar ones. Above the angle of the mouth there are others standing on 

 the serrated edge of the ridge, which latter expands backward across the 

 opercles and supports a prominent angle opposite the forward edge of 

 the eye, a more prominent one opposite the hinder part of the orbit 

 and another at the end of the gill cover, the last one preceded by a small 

 one in the indentation. Opercular spine, strong, sharp ; suprascapular 

 ridge low, rough. A serrated ridge immediately above the upper jaw is 

 divided into two above the articular; a lower ridge starting behind the 

 angle of the mouth forms three sections, of which the middle one is small. 

 Scales rough, granular, wider than long, with strong compressed hooked 

 blade-like spines, nine or ten of those in the second row on the back 

 of the tail sending a cusp forward as also backward. The spines make 

 four keel-like series the second of whicli forms a continuation of the 

 lower postorbital keel, curving downward behind the head till on the 

 level of the opercular spine, and the fourth of which continiies the keels 

 of the abdominal plates from the pectorals. Lower surface naked in 

 advance of the pectorals, covered with large granular laterally ridged 

 plates backward. A prominent genital papilla. 



Body red in life, more or less vermilion, throat and abdomen whitish, 

 upper half of the dorsal on the larger specimens black. On the young 

 specimens from which fig. 2, Plate A, is drawn the rostral processes and 

 the outer barbel are much shorter, the former only half as long, the 



