216 ZOOLOGY. 
cataractus, or the fall fish of Pennsylvania, attains to a considerable size, 
perhaps larger than that of any other allied form in this country ; specimens 
have been seen nearly two feet in length, and weighing several pounds. 
This size is, however, exceeded by many of the European species. The 
peculiar genus Hzoglossum is characterized by a trilobed lower jaw, the 
middle lobe formed by the extremity of the lower jaw, the lateral by cartila- 
ginous expansions. Another interesting sub-family, embracing several 
genera and many species, is that of the Suckers, or Catastomi. known by 
the highly fleshy lips, which can be applied to any object like a sucker. 
The pharyngeal teeth are columnar or prismatic, not hooked and truncated. 
They are found abundantly throughout North America; and different species _ 
are known by the various names of carp, sucker, mullet, buffalo-fish, red-_ 
horse, &c. Pil. 81, figs. 6,7, represent Cobitis fossilis and EK. barbatula, 
European species of a form not found in North America. 
The concluding family of the order Malacopteri, or Physostomt, is found 
in the Situripa, represented in North America by the catfish. Fishes of 
this family have the skin either naked. and covered with a slimy secretion, 
or provided with osseous plates of various number and shape. The head 
is usually depressed, and provided with a variable number of barbels. In 
most, there is a second and adipose dorsal, sometimes confluent with the 
caudal. The first rays of the dorsal and pectoral fins are generally enlarged 
into strong spines; and the pectoral spine is capable of being inflexibly 
fixed, by peculiar mechanism, in a direction perpendicular to the axis of 
the body. The edge of the mouth is formed by the intermaxillaries sus- 
pended from the sides of the ethmoid, which enters into the outline of the 
mouth, forming the superior median portion. The sub-operculum is absent 
in the whole family. 
Species of this polymorphous family are found distributed throughout the 
globe. In Europe, however, there is found but one species, the Silurus 
glanis, or sheat fish. This species, interesting from the fact of its being the 
largest fresh-water fish in Europe, the sturgeons excepted, is most abundant 
in central Europe, its existence in England being hypothetical. The weight 
has been known to exceed 100lbs., in this respect equalling some of the 
American Siluride. It differs from the North American species in the 
absence of a posterior adipose dorsal, in the very small true dorsal, and 
in the very long anal. Other species of this restricted genus, Silurus, are 
found in various parts of Asia, and perhaps Africa, but not in America. 
The American forms are highly varied, those of the northern continent, 
however, being quite uniform in structure. The two most conspicuous 
fresh-water genera are Pimelodus and Noturus ; the former with a distinct 
adipose dorsal, the latter with this dorsal confluent with the caudal. 
Numerous species of Pimelodus (cat-fish, horned-pout, bull-head) occur 
in the various waters of North America, some of which acquire a large 
size. One species, from the Mississippi, has been known to weigh over 
100ibs. The flesh of many species is highly prized, owing to its sweetness 
and freedom from bones. The genus Voturus, known provincially as stone 
cat-fish, embraces but few species, found in the Atlantic streams south of 
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