57 
those called yearlings. I entirely agree with Mr. Rave- 
ret-Wattel and the Scotch pisciculturists. If there is 
‘war, soldiers should be sent out, not babies; it is not the 
number which assures success, but the age and valor of 
the soldiers. Leaving this figure, which, however, shows 
the reason for employing yearlings, I venture to assert 
that if thissystem gains ground, the old system of stock- 
ing rivers should also be abandoned at Piedra, and the 
new system introduced. There will be no lack of food 
for the yearlings, for in digging out new ponds fed by 
the Devil Rock Brook it will be found that after two 
months they will be filled with cresses and other aquatic 
plants; and underneath these plants large numbers of 
-small shrimps will be found, as has been the case in all 
ponds which have been dug, where many millions of 
these small crustaceans are caught every year. 
In some places where the water freezes, the reproduc- 
‘tion of the crustaceans is possibly suspended for some 
time. I cannot state this with absolute certainty, for I 
have not had occasion to make the necessary observa- 
‘tions; but it seems to me that ice would not favor repro- 
‘duction. In the lake and in the Devil Rock Brook the 
temperature, even during the severest winter weather, 
never falls below fifty degrees. This is really a spring 
temperature and I have with my own eyes seen small 
‘shrimps reproducing in winter as well as during the other 
‘seasons of the year. I doubt whether there is any other 
place as highly favored by nature for raising salmonoids, 
and also cyprinoids (tench, barbel) and crawfish. 
Where the small shrimp is not found and the water 
‘contains particles of lime, attempts should be made to 
introduce it and favor its reproduction. 
