202 SPORT IN NORWAY. 
them the appearance of being wrapped in cotton. 
These should be removed, as, though the other eggs 
will not be immediately infected, yet-the fibres of this 
vegetable growth will in time get around them, and 
prevent the water having free access to them, when 
they, too, will die. The unfruitful salmon eggs should ~ 
be at once removed; but when the ova are very small, 
as is the case in trout, &c., it is better to wait till the 
parasitical plant has appeared before removing “ the 
tares from the wheat,” as the operation can then be 
performed more easily. It is therefore much better not 
to have a layer of small stones at the bottom of the 
case, as many of the ova will sink between them, and 
from remaining unperceived may in time cause great 
damage. It is true that the salmon instinctively makes 
a hole and covers her ova with small stones. But she, 
in all probability, only adopts this precaution in order 
to protect them against their numerous foes, and not 
that the development of the embryo may be thereby in 
any way accelerated. 
ON THE TRANSPORT OF OVA. 
It might not unnaturally be supposed that it is best 
to transport the ova in the same element as that in 
which they are deposited in the ordinary course of 
things, viz., 7n water. But it must at the same time 
