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Some observations on the Charr {Salmo umbla,) relating 

 chiefly to its Generation and Early Stage of Life. 

 By John Davy, M.D., F.R.S. Lond. &Edin., Inspector- 

 General of Army Hospitals. 



The observations contained in this paper are given under several 

 heads : 1st, on the roe and milt of the Charr ; 2dli/, on the time 

 required for hatching the ova, and on the young fish in progress 

 after exclusion ; 3dli/, on some agencies and circumstances supposed 

 likely to exert an influence on both. 



The principal facts which the author considers as established by 

 his observations are the following :— 



1st, That the time required for hatching the ova is variable, rang- 

 ing from about forty to ninety days, according to the temperature of 

 the water. 



2c?, That after exclusion the young fish can live at least sixty days 

 without taking food, deriving the material required for its support 

 and growth from itself, and chiefly from the store contained in its 

 yolk. 



3c?, That under favourable circumstances it attains its perfect form 

 in from about sixty to seventy days, when it becomes dependent 

 for its subsistence chiefly on food which it has to seek or procure 

 from without. 



4th, That running water is not essential to the hatching of its ova ; 

 and in consequence of its breeding place being distinct from that ot 

 the trout, it is exposed to little risk of being lost as a species by re- 

 peated crossings with the trout. 



5tfi, That salt water, even of greater saltness than sea water, is not 

 immediately fatal to the embryo ; that a partial development of the 

 ovum may take place in brackish water ; and that young fish can 

 exist some days in such water, rendering it probable that the adult may 

 be capable of living in a tidal stream, or even in the sea, where it is 

 stated that the Welsh Charr has been caught. 



6th, That the young charr can endure confinement for several days 

 in water of small bulk, such as may be used for transporting it from 

 place to place, especially if oxygen gas be supplied in the place of 

 common air. 



7th, That tlie young fish can bear without any immediate apparent 

 Injury, a temperature removed only a degree or two from the freezing- 



