182 The Nematognathi, or Catfishes 
meridionalis, as far south as Rio Usamacinta on the boundary of 
Guatemala. 
Besides these, a large channel-cat of peculiar dentition, 
known as Istlarius balsanus, abounds in the basin of Rio Balsas. 
In Mexico all catfishes are known as Bagre, this species as 
Bagre de Rio. 
The genus Leptops includes the great yellow catfish, or 
goujon, known at once by the projecting lower jaw. It is a 
mottled olive and yellow fish of repulsive exterior, and it reaches 
a very great size. It is, however, a good food-fish. 
The Mad-toms.— The genera Noturus and Schilbeodes are 
composed of diminutive catfishes, having the pectoral spine 
armed at base, with a poison sac which renders its sting ex- 
Fic, 145.—Mad-tom, Schilbeodes juriosus Jordan & Meek. Showing the poisoned 
pectoral spine. Family Siluride. Neuse River. 
tremely painful though not dangerous. The numerous species 
of this genus, known as “mad-toms’”’ and ‘stone cats,” live 
among weeds in brooks and sluggish streams. Most of them 
rarely exceed three inches in length, and their varied colors 
make them attractive in the aquarium. 
The Old World Catfishes.—In the catfishes of the Old World 
and their relatives, the adipose fin is rudimentary or wanting. 
The chief species found in Europe is the huge sheatfish, or wels, 
Silurus glanis. This, next to the sturgeon, is the largest river fish 
in Europe, weighing 300 to goo pounds. It is not found in Eng- 
land, France, or Italy, but abounds in the Danube. It isa lazy 
fish, hiding in the mud and thus escaping from nets. It is very 
voracious, and many stories are told of the contents of its 
stomach. A small child swallowed whole is recorded from 
Thorn, and there are still more remarkable stories, but fot 
