FISHES. 115 



received in a cavity behind the gill-cavity proper. The head is mailed above, the 

 body naked ; there are eight barbels, and the mouth is of moderate size. " The 

 skeleton is formed by a soft, cartilaginous substance covered by mucous membrane, in 

 which the vessels are embedded." The species inhabit the mud and swamps of 

 India, East Africa, and the East Indies. They are among the largest of the Nematog- 

 nathi, some of them reaching a length of six feet. Nearly thirty species are known. 



The PiiOTOsiD^ (including CsAciDiE) are naked cat-fishes, with a short first dorsal 

 above the pectoral, and a very long second dorsal, which is similar in form to the 

 anal, and is connected with the latter around the tail. The gill membranes are 

 united and free, or more or less joined to the isthmus, and barbels are developed 

 around the mouth, which is commonly large. About a dozen species are known, from 

 the fresh or brackish waters of India, Australia, and Polynesia, most of them entering 

 the sea. They reach a length of one or two feet. 



The great majority of the Nematognathi belong to the typical family of Silueid^e, 

 which, even in the restricted sense in which it is understood by Dr. Gill, contains 

 upwards of one hundred genera, and over seven hundred species. The members of 

 the family agree in having the skin naked or imperfectly mailed ; the opercukim 

 present; the dorsal fin short (rarely wanting), inserted above or in front of the 

 ventrals ; the adipose fin without spine (rarely wanting) ; the lower pharyngeals 

 separate ; the barbels about the head well developed. Members of the family are 

 found in all parts of the world where any of the order of N'ematognathi occur. To 

 this family belong all of the marine species. In the present work we can only glance 

 at the principal sub-families and some of their leading genera. 



The typical sub-family, or Silurinte, has the dorsal fin very short and the anal fin 

 very long, while the adipose fin is rudimentary or wanting. The gill membranes are 

 more or less free from the isthmus. The species of this group belong entirely to the 

 Old World, being especially abundant in the fresh waters of the East Indies, 

 Southern Asia, and Africa. Eighty species are enumerated by Dr. Gtinther. A 

 single one is found in Europe, being tlie only Siluroid fish in that region. This is 

 Silurus glanis, the Wels of the Germans, the Saluth of the German Swiss, the 

 sheat-fish of the English, the Silurus of the Latins, ^ilovqoi or ri.uvtg of the Greeks. 

 Next to the sturgeon, the /Silurus is the largest fish in Europe, reaching at times 

 a weight of three hundred to four hundred pounds. In its distribution it is confined 

 to central and eastern Europe, not being found in Great Britain, Prance, Spain, or 

 Italy. Valenciennes speaks of it as a lazy fish : " it holds itself in the depths on 

 bottoms of clay or mud ; it hides itself there, and is warned of the approach of its 

 prey by means of its barbels ; this renders it difficult to take by means of nets, as the 

 latter pass over it. In times of storm it rises to the surface, and thus it happens that 

 it is sometimes strewn on shore by the waves. 



"It is very voracious. It is said that of all fishes it spares only the perch, and 

 this because of its spines. It destroys many aquatic birds, and it is said that it does 

 not spare even the human race. On the 3d of July, 1700, one was caught by a 

 peasant at Thorn, which had a small child whole in its stomach." Stories are also 

 told of its having swallowed whole children and young girls in Hungary, and in 

 Turkey even a grown woman, with a ring and a purse full of gold ; but I fear, how- 

 ever, that on these cat-fish stories we must draw the line somewhere. 



The Bagrinse have a short dorsal fin placed in front of the ventrals, a long adipose 

 fin, a short anal fin, teeth on the palate, the gill membranes free from the isthmus, and 



