690 REPORT OF COMMISSIONER OF FISH AXD FISHERIES. 



have been altogether too "artificial"; our whole system of pisciculture 

 has been too "artificial."' 



The chief mistake which we have made in all our piscicultural efforts 

 is this : that we have principally used the convenient, pure, and clear 

 spring water in our hatching apparatus. 



It is true that a piscicultural establishment using only such clear 

 spring water presents a very pretty appearance. The eggs lie in water 

 transparent as crystal; they can be distinctly seen at all times; the 

 water is never muddy ; no sediment ever disfigures the eggs. Altogether 

 such a piscicultural establishment is a thing of beauty. 



The pisciculturist can tell you accurately that on the twenty-fourth or 

 twenty-fifth day the eye-dots become visible in the egg ; he can calcu- 

 late almost to the minute when the first young fish will be hatched ; he 

 even knows, when he places the impregnated eggs in the water, when 

 the young fish will have lost their umbilical bag and when the appa- 

 ratus will be ready to receive other eggs. Such a hatching apparatus, 

 furnished with clear spring water, is very convenient indeed, if it has 

 an even temperature of -f 7 to 8° Reaumur. 



The poor pisciculturist, however, who has to work with brook water, 

 often has to wait one hundred days instead of twenty-three or twenty- 

 four, before he can see the first eye-dots in his eggs ; then many, many 

 days have to elapse until the young fish are hatched and have lost their 

 umbilical bag. How often does it happen moreover, that the most care- 

 fully arranged filtering apparatus does not make the water quite clear. 

 In the muddy water the eggs and young fish are frequently not to be 

 seen! and then the endless time till the hatching process is finished ! 



Whilst the whole development of the embryo can be finished in six 

 weeks in the beautiful clear spring water having a temperature of 8° 

 Keaumur, it often takes six months in the cold, muddy, and ugly looking 

 river water! 



Who would not under these circumstances prefer the beautiful spring- 

 water ? 



And still ! 



The spawning season of the trout and salmon commences about the 

 end of October and lasts till the middle of November. The piscicultur- 

 ist who works with spring water must therefore place his young fish in 

 the water towards New Year, whilst he who works with river water can- 

 not do this till the end of April or the middle of May. 



Which of the two is to be preferred under these circumstances ? 



The first food of the young salmonoids, and probably of most fish, are 

 small crustaceans (Cyclops, Daphnia. &c). Most of these diminutive ani- 

 mals, which fill the water in enormous quantities, had in autumn cared 

 for the propagation of their race by laying winter eggs. They then bid 

 adieu to this hard world and died. They departed this life with the con- 

 soling hope that the life-bringing sun of spring would from the eggs laid 

 in the mud, where they would peacefully rest all winter, produce lively 



