130 MEMOIRS OF THE CARNEGIE MUSEUM 



bb. Nares remote; barbels six; adipose fin well-developed. 



I. Teeth incisor-like, in two series in the upper, in a single series in the lower jaw. First dorsal 



and pectoral raj's not spine-like; adipose long {Callophysirue) Callophysis. 



a. Teeth villiform, in ha,nds (Pimelodin(B.) 



j. Vomer without teeth or with teeth in minute patches. 



k. Snout broad and produced, spatulate. Adipose short. First ray of the dorsal and 

 pectoral fins articulate, not pungent, prolonged in filaments; barbels flat, 



not fringed Megalonema. 



kk. Adipose fin very long, barbels flat, ribbon-like; dorsal and pectoral spines not 



pungent, the dorsal spine produced Pinirampus. 



kkk. Snout not produced, barbels not flat. 

 I. Orbit without a free margin. 



m. Dorsal and pectoral spines strong, pungent; body short. 



n. Dorsal surface of skull covered with thin skin; head about as broad 

 as long; origin of ventrals behind middle of body, except 

 sometimes in the young; sometimes a small circular fontanel 

 at base of occipital process; frontal fontanel not extending 

 backward behind the eye. 

 0. Premaxillary patch of teeth with a backward projecting angle. 



Pseudopimelodus. 



00. Occipital crest very short, not nearly reaching dorsal; premaxillary 



teeth without a backward projecting angle on the sides. 



Species with a light band across the occiput. . . Microglanis. 



nn. Dorsal surface of skull covered with a thick layer of muscle; occipita' 



crest short; origin of ventrals in front of middle. . . Brachyglanis. 



mm. Pectoral spines strong but short; dorsal spines small or replaced by a 



soft ray; skull covered with a thick laj'er of muscle; anal 17-21, 



body long, slender; occipital crest short.* 



p. Caudal rounded; an occipital, no frontal fontanel; ventrals under 



posterior half of dorsal Leptoglanis. 



pp. Caudal forked; ventrals under posterior half of dorsal; a median 

 ridge from the frontal fontanel to the occipital process; caudal 

 without accessory rays, lower caudal lobe longer; adipose 



reaching caudal Myoglanis.' 



mmm. No dorsal or pectoral spines; upper surface of head covered with the 



skin only; fontanel a narrow slit continued to base of occipital 



process; ventrals entirely under the dorsal or partly in front of it. 



much nearer snout than to caudal, bodj' long and slender. 



q. Caudal rounded Heptapterus.' 



'Skull covered with thin skin; A. 9. Imparfinis. 



' It is probable that Heptapterus coUetii Steindachner "with the ventrals under the origin of the 

 dorsal; upper caudal lobe longer; caudal with fulcra; adipose not reaching caudal" should be the type of 

 another genus. 



' The genus Heptapterus Bleeker, so far as known with certainty, is confined to southeastern tropical 

 America. It consists of the following species: Heptapterus mustelinus Valenciennes, from Rio Grande 

 do Sul and the lower La Plata, and Heptapterus eigenmanni Steindachner, from Maldonado. 



