62 AMERICAN FISH CULTURE. 



figure 1. Looking down on the egg, the speck is seen in 

 the centre, apparently on top, as in figure 2. 



" Seven days after the ova is taken, (the water at 47°), a 

 small circle is seen around the speck, whether the egg be 

 impregnated or not, and the two are so much alike at this 

 stage, that it is difficult to know which are the fecundated, 

 and which are not, and yet a very close examination will 

 show a difference. The fecundated egg has a clearer speck 

 in the centre, and the ring around the speck is larger, as 

 will be seen by referring to figure 3. The unimpregnated 

 is illustrated by figure 4. 



" When nine days old, the circle in the impregnated egg 

 has enlarged, a slight brownish or bluish gray tinge per- 

 vading the interior ; the germ having spread over a sixth 

 part of the egg, presenting the appearance of figure 5 ; 

 while the unimpregnated still remains as pictured in figure 

 4. The latter never change after the ninth day, unless to 

 become opaque, which they continue to do during the in- 

 cubation of the fecundated ova, and are as easily distin- 

 guished from them in the hatching-troughs as a few white 

 beads would be if scattered amongst those of transparent 

 glass. 



" On the eleventh day, the first formation of the fish can 

 be seen ; a brown line extending from the circumference 

 towards the centre of the circle, which now covers one- 

 third of the egg. The appearance of the egg at this time 

 is exhibited, up by figure 6, and sideways by figure 7. 



" When twelve days old the circle will be seen to cover 

 one-half of the egg. Front view shown by figure 8, side 

 view by figure 9. 



