180 FISH CULTURE. 



ever, nearly approaching the Powan in that respect. 

 There is an excellent fish of this class, called the 

 Pera, found in Lake Geneva. This delicious fish has 

 engaged the attention of French pisciculturists, who 

 have heen , largely occupied in stocking many of the 

 most convenient and contiguous waters of France with 

 it. The French Government are very liberal in trans- 

 mitting fecundated eggs of the Fera upon application ; 

 and there can be little doubt but, in a few years, we 

 shall number this fish amongst our Fauna. There is 

 another fish of this class, called the Lavaret, found 

 in the Swiss Mkes, which is highly spoken of for the 

 table. It has been asserted by some that it is identical 

 with the Fera — ^by others that it is also identical 

 ^ith the Gwyniad ; but it is, I believe, now decided 

 that it is a separate variety. Carl Voght distin^ 

 guishes it from the Fera : (his description of both 

 these fish will be found in the Appendix.) 



Unfortunately, the whole tribe of Coregoni are but 

 imperfectly known, and there has hitherto existed 

 considerable difficulty in the way of comparison. 

 One point with regard to them is indisputable — ^viz. 

 that many of them are very desirable fish to culti- 

 vate, as the food they consume is composed of 

 insects, such as the smaller Coleoptera and the Ento- 

 mostracee. The Coregoni are said to abound iu mar^ 



