FISHES. 39 
Oss. The name of Uhrichomycterus was first framed by Humboldt,* under the following circum- 
stances: Having obtained a fish from the Rio Bogota, in New Grenada, he published a memoir 
thereon, in which he says: ‘‘ Je l’ai nommé érémophile, 4 cause de la solitude dans laquelle il 
vit 4 de si grandes hauteurs, et dans des eaux quine sont presque habitées par aucun ¢tre vivant. 
Les naturalistes qui craignent que de nouvelles espoces de ce méme genre ne viennent A étre 
découvertes dans des situations trés-différentes, pourraient changer le nom d’érémophile en celui 
de thrichomycterus, tiré des barbillons attachés au nez de ce poisson.”’ 
Thrichomycterus, therefore, in the estimation of Humboldt, was exactly the synonym of 
Eremophilus. 
Now, in the second volume of the same work, Valenciennes, after giving us a more complete 
description of Hremophilus mutisii, mentions that another fish, generically distinct from the 
above, had been obtained from Brazil, and for which he would propose the name of Z'hricho- 
mycterus, imagined by Humboldt. 
No reference to the history of this generic name being made in the Histoire Naturelle des 
Poissons, we have considered ourselves fully justified in relating it here. The transfer of a 
name to a thing for which it was not originally intended, if not explained, is liable to throw 
a great deal of confusion upon the subject it refers to, and is likewise an infraction to sound 
rules of nomenclature. 
Many species having been described under the name of Vhrichomycterus, we would advise 
that it should be retained, rather than to frame another one. The species of T'hrichomycterus 
are closely allied to Hremophilus, from which they chiefly differ by the presence of ventral fins. 
THRICHOMYCTERUS MACULATUS, Cuv. et Val. 
Pirate XXXIV, Figs. 1—3. 
Spec. car. Head small and very depressed, declive towards the snout, which is anteriorly 
rounded. Mouth small. Maxillary teeth inconspicuous. Upper buccal barbel longer than the 
lower, neither of which reaching the base of pectorals. Prenasal barbel as long as the upper 
buceal. Opercle and subopercle prickly. Isthmus quite small. Branchiostegals, six. Caudal 
subemarginated posteriorly. Skin perfectly smooth. Ground-color yellowish or brownish, 
maculated with black. Fins greyish yellow. 
Syn. Vhrichomycterus maculatus, Cuv. et Vau. Hist. Nat. Poiss. XVIII, 1846, 493. 
Guicu. in Gay, Hist. de Chile, Zool. II, 1848, 311. 
GrrarD, in Proce. Acad. Nat. Sc. Philad. VI, 1854, 199. 
Bagre, or Vagre. Vernacular. 
Desc. The species is one of small size. The body is slender and elongated, anteriorly rounded, 
and slightly compressed; posteriorly more so. The greatest depth, measured immediately 
behind the tip of pectoral fins, is contained nearly nine times in the total length, and the least 
depth, taken on the peduncle of the tail, enters in that same length thirteen times. The great- 
est thickness, at the anterior portion of the body, is about equal to the depth. The head is 
contained six times and a half in the total length. It is much depressed, wedge-shaped, and 
equally declive towards the sides. The snout is anteriorly rounded. The upper jaw overlaps 
the lower, thus giving the mouth an inferior situation. The latter is small, and surrounded 
with thick and fleshy lips, but little extensible upon the upper jaw. A membranous expansion 
is to be observed at the angle of the mouth, immediately below the barbels. The latter are 
* Recueil d’Observations de Zoologie et d’Anatomie Comparée, &c., Vol. I, 1811, 18. 
