ZOOLOGY. 291 



swaying of the great caudal fin gives them a serpentine 

 course." It is doubtful whether they ever go quite out of 

 the water to graze, as has been so often reported ; for they 

 are too bulky to progress by their fins, and not sufficiently 

 elongated to go snake or eel fashion, and they also evince 

 dislike to being kept out of water for any length of time. 



The Catfishes. 



The species of catfishes occurring in our fresh waters have 

 received the attention of Professor Jordan, and to him are we 

 indebted for a thorough and much-needed revision. Profess- 

 or Jordan adopts the group, as well as the genera, estab- 

 lished by Gill, and recognizes thirty species within the United 

 States. These species belong to four genera, which are, on 

 the whole, very well marked. (1) The common catfishes the 

 stout-bodied and rounded or square-tailed species belong 

 to the genus Amiurus : of these there are seventeen species; 

 (2) the channel cats slender, forked-tail species are three 

 in number, the most common and widely diffused being Ich- 

 thmlurus fureatus y (3) the mud-catfish of the Ohio valley a 

 very long, depressed, and mud-colored fish represents alone 

 the genus Pelodichthys ; finally, (4) the stone-cats distin- 

 guished by an eel-like tail and flat head marked by a crucial 

 depression behind represent the genus J\ r oturus, of which 

 there are eight species. The common error that the largest 

 species of the family is a channel cat has been corrected by 

 Professor Jordan, and it is shown that the great catfish of 

 the Mississippi valley is not an Tchthodurus, but an Amiurus, 

 and the same as the Amiurus nigricans of the Great Lakes. 



Slickers. 



The so-called "Suckers" of the American fresh waters con- 

 stitute a family rich in species in the United States, but else- 

 where only found (under two generic types) in Northeast- 

 ern Asia. Twelve distinct genera are now known, and not 

 the least interesting of them is one lately discovered by Pro- 

 fessors Jordan and Braxton during a tour made throuo-h the 

 Southern States in the interests especially of ichthyology. 

 The newly acquired form has the usual Catastomid physiog- 

 nomy, but is distinguished by a very peculiar lower jaw and 

 lip. The jaw is deeply split in the middle, and thus has the 



