402 RIVER TROUT SALMON. Class IV. 



some of the Cambrian fishes, published in the 

 Philosophical Transactions of the year 1767- 



The stomachs of the common trouts are un- 

 commonly thick, and muscular. They feed on 

 the shell-fish of lakes and rivers, as well as on 

 small fish. They likewise take into their sto- 

 machs gravel, or small stones, to assist in com- 

 minuting the testaceous parts of their food. 

 Gillaroo The trouts of certain lakes in Ireland, such as 

 those of the province of Galway, and some 

 others, are remarkable for the great thickness of 

 their stomachs, which, from some slight resem- 

 blance to the organs of digestion in birds, have 

 been called gizzards : the Irish name the species 

 that has them, Gillaroo trouts. These stomachs 

 are sometimes served up to table, under the 

 former appellation. It does not appear to me, 

 that the extraordinary strength of stomach in 

 the Irish fish, should give any suspicion, that 

 it is a distinct species : the nature of the waters 

 might increase the thickness ; or the superior 

 quantity of shell-fish, which may more frequent- 

 ly call for the use of its comminuting powers 

 than those of our trouts, might occasion this 

 difference. I had the opportunity of comparing 

 the stomach of a great Gillaroo trout, with a 



* PhUosoph. Transac. Vol. LXIV. p. llG, 310. Soto. Br. 

 Misc. tab. 6l. 



