1878.] 677 [Cope. 
bust, denticulated in front ; pectoral spines twice as long, equaling (axial) 
length of head, robust, and serrate on both edges. Their extremities ex- 
tend behind the line of the last dorsal ray, but do not reach the origin of 
the ventral fin. Caudal fin truncate with a slight obliquity inwards and 
downwards. Total length M. .230; of dorsal spine .023 ; of pectoral fin 
.045. Color above blackish, below brown ; lower part of sides, chiefly be- 
hind pectoral fin with dark spots on the brown ground. ~ 
This robust species is related to such as the A. obscurus Gthr., but dif- 
fers from them in the short beards, fewer fin rays and other characters. 
Coll. 1877. 
18. AUCHENIPTERUS ISACANTHUS, sp. Nov. 
Head rather wide, not steeply shelving at the sides posteriorly, and 
finely rugose ubove, without a dermal layer, so that the segmentation of 
the bones is distinctly visible. Its length enters the total (less caudal 
fin) four times; which is an expression of the robust form of the fish. 
The body is highest at the front of the anal fin. Radii D. I. 5; A. 22; 
V. 7%. Dorsal and pectoral spines of equal length and a little shorter 
than the length of the head, both serrate on both edges, the dorsal much 
the more finely. Eye obscure; operculum covered with smooth skin. 
Anterior mental barbels about equal to diameter of orbit ; maxillary 
barbels reaching end of pectoral spine. Mandible projecting a little be- 
yond premaxillary. Humeral process reaching beyond the middle of the 
pectoral spine, its surface coarsely striate, the striz nodular. No thoracic 
dermo-ossification. Anal fin with nearly straight free border. Total length - 
.085 ; of head above .025; of dorsal spine .016; interorbital width .C11. 
Uniform lead color ; dorsal fin with a black spot above. 
This species is much smaller than the last, and very different in many 
respects, although it agrees with it in the rugosity of the head. It has, 
however, a large fontanelle open in front, while that of the A. brevibarbis is 
very small, and completely enclosed. 
Two specimens ; Coll. 1877. 
19. CENTROMOCHLUS NECKELI! Filippi. 
Coll. 1877. 
20. EPAPTERUS DISPILURUS, gen. et sp. nov. 
Char. Gen. Group Doradine of Gunther, with anterior dorsal fin in 
front of the ventrals, and gill membranes confluent with that of the throat. 
No adipose fin ; soft portion of dorsal rudimental. Six barbels; teeth want- 
ing from jaws and palate. Dorsal and pectoral spines present ; ventral fins 
united to each other and to the middle line of the belly. Anal fin long, 
distinct from the caudal. 
This new genus is related to Huanemus, but is distinguished by three 
characters, viz: (1) absence of adipose fin; (2) absence of teeth, and (8) 
rudimental soft part of first dorsal fin. The rudimental character of the 
teeth in Huanemus nuchalis offers an approximation to the edentulous con- 
dition of Hpupterus. 
