1864.] ON PISCICULTURE. 143 



In a common wooden box the moss will retain its dampness so 

 as not to require wetting for several days. And indeed caution is 

 requisite when it is so sprinkled, that the temperature of the fresh 

 water be not lower than that of the moss. Moreover, it is only 

 necessary to sprinkle the topmost layer of the moss, as the mois- 

 ture will gradually percolate through the contents of the box. 

 Neither should too much water be sprinkled on at one time, lest 

 the ova at the bottom of the box should be immersed. To obviate 

 this contingency, it is best to turn the box over once at least in the 

 course of the day. 



In packing the box, the bottom should first be evenly covered 

 with a thick layer of the moss, which should be previously washed 

 quite clean. On this a layer of eggs should be evenly spread, then 

 irhould come a thinner layer of moss than before, and so on, alter- 

 nate layers of eggs and moss till the box is nearly full. On the 

 top of all, a layer of moss of the same thickness as the first should 

 be laid ; so that when the lid is fastened down, the whole will form 

 a compact mass, and all shifting of the contents be rendered im- 

 possible. The elasticity of the moss will prevent the slightest 

 danger from pressure accruing to the ova. If the weather is ex- 

 tremely severe, the box should be protected. It may be remarked, 

 that ova should not be transported till the eyes of the embryo are 

 visible. 



A few precautions are necessary on unpacking such a box con- 

 taining ova. The temperature of the box, and of the water in the 

 hatching-case, must be compared with a thermometer. Supposing 

 that of the former to be the greater, the moss should be gradually 

 sprinkled with water from the latter till they are both equal. 

 Great care must be taken not to hurry this operation. 



The contents of the box should then be emptied into a good- 

 sized tub half filled with water of the same temperature as that in 

 the hatching -case. By gently moving the hand about among the 

 moss, the ova will sink to the bottom, and the moss remain float- 

 ing on the surface. The water should now be drained off, and the 

 ova at once deposited in the hatching-boxes. 



Should the water in the hatching-boxes, however, be of a higher 

 temperature than the moss in which the ova were conveyed, these 

 can be at once removed into the hatching-cases after they have 

 been detached from the moss as above described. 



