MANUAL OF FISH-CULTURE. 51 



The latter procedure is attended to for the entire stock of eggs, but 

 is of special importance in case of those that are to be transported. It 

 may be performed any time after the good eggs become hardy — that is, 

 after the eyes become black — but becomes easier late in the season. The 

 unimpregnated eggs, which were at first fullj^ equal in hardiness to the 

 impregnated, lose in that respect as time passes, and finally are readily 

 killed and turned white by a shock which does no injury to the impreg- 

 nated eggs. When this time has arrived, the eggs are turned from the 

 trays into spawning-pans with a moderate quantity of water, and 

 poured from pan to pan back and forth a dozen times, each time falling 

 a foot or more, and striking the bottom of the pan with considerable 

 force, giving each egg a severe shock. They are then returned to the 

 trays and troughs and as soon as convenient are picked, and if the 

 operation has been thorough almost every unimpregnated egg has 

 turned white and is picked out, while the eggs in which the embryos 

 are developing have not sufiered at all. 



PACKING AND TRANSPORTING. 



Eggs may be safely transported as soon as the eyes have become 

 thoroughly colored, and until within a few weeks (five or six in cold 

 weather) of the date for hatching. In shipments made too late the shells 

 burst on the way and the embryos perish. The method of packing eggs 

 at Craig Brook is to put them in layers alternating with wet sphagnum 

 moss in shallow wooden boxes, placed in cases of a size to afibrd on 

 all sides of the inner package a space of 2i or 3 inches, which is filled 

 with some light, porous material that will form a good nonconductor 

 of heat. 



The eggs are thrown from hatching- trays into a large rectangular 

 pan, from which they are poured with water into tin measures which 

 hold 2,500 each. A thin layer of moss is placed in the bottom of a 

 l^acking-box. A little fine snow is sifted upon the moss, and on this is 

 spread a piece of mosquito netting that has been soaked and rinsed in 

 clean water. A measure of eggs is now poured on and spread out and 

 covered by folding over the edges of the netting, which now completely 

 envelops them. 'Next a layer of moss is spread, followed by snow, 

 netting, and eggs, as before, and the series is repeated until the box is 

 fall. The moss must be sufficiently wet, so that with the melting of the 

 snow it shall have all the moisture it will hold, and no more, as it is 

 very desirable to avoid the wetting of the outer packing. If the 

 moss is too dry, the eggs may dry to the extent of becoming indented, 

 and the same result may come from crowding the moss in too hard on 

 the eggs, though it should be pressed in so tightly that the eggs will 

 not slide out of place if the case is turned for a moment on its side. 



The temperature of the packing-room is below 50° F., and packing 

 materials are kept in a place which is cool, yet not much below the 

 freezing-point. Salmon eggs packed as above commonly go a three 

 days' journey without completely meltiug the snow that was sprinkled 



