CHONDROSTOMA NASUS. 193 



The Tench was formerly used for external application in medicine, being- 

 held to absorb poisons from the body, or act as a poultice. The older writers 

 regarded the Tench as the fishes' physician ; and believed that it was therefore 

 spared by the Pike and other voracious fishes, but anglers find it to be an 

 excellent bait ; and more than twenty young ones have been taken from the 

 stomach of a Trout. 



It is distributed in every European country, not only in the small sluggish 

 streams or muddy districts in which it especially abounds in England, but in 

 all rivers large or small, and in most of the lakes, if not in all. It is also 

 recorded from Brusa, in Asia Minor. 



GENUS : ChondrOStoma (AGASSIZ). 



This genus is almost limited to Europe. Distinct species occur north 

 and south of the Alps and in Spain, Italy, and the Balkan peninsula; 

 while another species extends its range farther east into Asia Minor, and the 

 valley of the Tigris. The characters which unite these species together into a 

 genus are, first, the presence of a hard, brown, horny covering to the lower 

 jaw, which forms a kind of beak ; and secondly, the pharyngeal teeth are knife- 

 shaped, not denticulated, and arranged in a single row, which may include from 

 five to seven teeth on each side, though occasionally the number of teeth on 

 the two sides is unequal. The scales are small. The lateral line terminates 

 in the tail. The dorsal fin, which is inserted above the root of the ventral, 

 has never more than nine branched rays. The anal fin has a rather elongated 

 base with not fewer than ten rays. The gill-rakers are short and fine. The 

 lining; membrane of the abdomen is black. 



Chondrostoma nasus (LINNJSUS). 



D. 12, A. 1314, V. 11, P. 1516, C. 19. Scales : lat. line 5762, trans. -J 



This species, which is absent from Britain, is widely distributed on the 

 continent of Europe, north of the Alps. It is also found in the Turkish rivers, 

 and in Russia throughout the river systems of the Black Sea, the Sea of Azov, 

 and the Caspian, and does not appear to extend beyond the Caucasus. It is 

 met with in the rivers which flow into the southern part of the Baltic. 

 It occurs throughout Germany, and in most parts of Austria, where it is 

 generally known as the Nasling. In France it is popularly recognised as 

 13 



