182 DESCRIPTION OF SALMON OVA. 



Let any one examine the roe* of a female 

 salmon about spawning time, and the peas, grains. 



* It would be exceedingly difficult to surpass for minute- 

 ness and accuracy the description of salmon ova given in 

 IMr. Young's pamphlet, and running as follows : — " Ova, 

 when extracted from salmon in spawning time are of a pale 

 or light blue colour, and each is about the size of a small 

 pea. It is composed of a white shell, and light red yolk, 

 and from the crystalline nature of the shell, the inward 

 parts of the egg are quite perceptible, — the shell being full 

 of small pores, scarcely discernible to the naked eye, 

 which, at the time of deposition, fully prepare it for the 

 reception of the milt of the male fish. At this time the 

 yolk of the egg, apparently filling the cavity of the shell, 

 gives it an uniform colour, rendering the external whiteness 

 of the shell scarcely perceptible. After the eggs have lain 

 twenty days in the gravel of the spawning-bed, the yolk 

 approaches more to white, and gives the whole egg a lighter 

 appearance. Now is discernible on one side of the yolk a 

 very small brilliant spot which increases in size, so that by 

 the time the eggs have lain thirty-three days amongst the 

 gravel, it has covered nearly a third part of the yolk. The 

 remaining part approaches more to white, and exhibits the 

 shell more clearly, so that the observer is very much inte- 

 rested in noting the visible alteration. The red spot grows 

 larger daily, and when the eggs have been forty eight days 

 in the gravel, the red spot has covered fully one-half of the 

 yolk, and continues to spread daily more and more. At 

 this period are first seen traces of the embryo fish, under the 

 appearance of an elongated formation of a bluish white, in 

 the yolk of the egg, and of about the thickness of a small 

 thread. The yolk being of a different colour we can clearly 

 see the formation increasing in size daily, and dri^wing more 



