APPENDIX. 



ward pressure as long as the eggs continue to come 

 out. If you find the eggs do not come out quite 

 easily, give the tail of the fish a gentle shake, to 

 loosen those eggs that still remain in the abdo- 

 men ; hut recollect if you use force, you will spoil 

 the experiment. The eggs must run out quite 

 freely. 



9th. The eggs heing collected at the bottom of 

 the vessel, take a male fish. Make pressure on the 

 abdomen, in the same way as has been done to the 

 female. If the melt is ripe, it will instantly dis- 

 colour the water, making it of a cream, or rather 

 milk-white appearance. Stir the eggs and milt 

 gently together, and leave them quiet for three or 

 four minutes, pour off the milk-coloured water, and 

 gently add fresh water, till the eggs appear quite 

 clear again.* If this has been properly and care- 

 fully done, the eggs have been thoroughly impreg- 

 nated. Place the eggs in the vessel by means of 

 which you intend to take them to the hatching 

 apparatus, and carry them in your hand, without 

 shaking. If you remain out a night, stand the 

 bottle or can with the eggs in a tub of cold water. 



As regards the number of males to females, be 

 sure to obtain sufficient males before you begin to 

 operate. The milt of one male will impregnate 

 the ova of many females ; but it is not wise to get 

 the eggs from a female, and then have no milt to 

 place with them. You can impregnate one lot of 

 eggs with a male, place him back into the temporary 

 reservoir, and use him for other lots of eggs. 



* Return the fish you have spawned to the river ; if you have 

 been neat-handed they will be none the worse for the opera- 

 tion. 



