How to obtain tt. 147 
number of good fish a couple of milters are selected—sometimes. 
one only is used, but as there are eggs from several females in the 
dish there is no harm in using more than one male, should it be 
deemed desirable to do so. Sometimes the milt may not be quite 
ripe, or may be spent, or stale, and in such a case the ova would 
probably not be impregnated. By taking a second or even a 
third male under such circumstances good eggs may often be 
saved. I have seen the time when good milt was difficult to 
obtain late in the season, even from the ponds of a well-ordered 
fish farm. 
These matters must be learned by practice and experience. 
It is as needful now-a-days for a would-be fish culturist first to go 
as a pupil to some first-class fish farm, as it is for anyone wishing 
to be thoroughly well up in agricultural pursuits to go and learn 
farming. There is much that cannot by any means be learned 
from books, and there is much also that one who is not already 
skilled in the work must be taught by an expert, not only 
practically but theoretically. A thorough knowledge of the 
development of the embryo under varied circumstances and 
surroundings is very essential, and can only be acquired by a good 
‘deal of thoroughly practical work with the microscope. 
When viewed through a high power immediately upon 
extrusion from the fish, the milt is found to contain an enormous 
number of minute organisms called spermatozoa, which at first 
are very lively, and move about rapidly by means of flagella. Very 
soon their activity begins to cease, and in less than a couple of 
minutes they usually cease to move. In one part of the shell of 
the ovum is a minute aperture called the micropyle, and by means. 
of this micropyle one of the spermatozoa is enabled to enter the 
egg and impregnation is effected. The reason for being. 
expeditious in the work will be at once apparent when these facts. 
are considered. 
During the first few weeks of their existence the eggs are very 
delicate, and a very slight shock or vibration will often so disturb. 
their organism as to kill them, but, strange to say, this does not 
apply to the first twenty-four hours or more after they are taken 
from the fish, during which time they will bear any reasonable 
amount of shaking, but are very sensitive to temperature. This. 
