NINTH ANNUAL MEETING. rit 
by hand, and were found to be ripe, but the eggs were all crush- 
eed in passing from them. The vent of the ovaries or ovaduct 
was too small to allow the eggs, which had delicate shells, to 
pass. Attempts were then made to enlarge the vent, and some 
thousands of eggs were finally obtained in this way uninjured. 
To impregnate these the milt of the male trout was used. The 
parent fish were left in their pond and seemed to be uneasy. 
They are doubtless incommoded by the eggs which they cannot 
pass, and move about slowly with their heads towards the bot- 
tom, their tails upward, and their bodies at an angle to the sur- 
face. The eggs which it was hoped might be impregnated by 
hand, were retained until January 25th, 1880, when it was found 
they were unimpregnated and dead, and they were thrown away. 
No eggs have yet been deposited in the regular way, and hybrids 
have not yet hatched. But two most extraordinary facts have 
been ascertained : one, that the eggs may be too large for extru- 
sion; this may only be the case when the father is the larger 
fish; and the other that the entire body of one hatching may 
belong to a single sex. I[t is said that the shad-herring hatched 
on the Hudson are all males. This may be the end of the per- 
petuating of new breeds of fish, or it may be only the beginning. 
It does not follow that every batch of a cross, especially when 
taken in different years, will be of the same sex, nor that the 
eges will be too large when the male is the smaller variety. As 
was mentioned before, the hybrid takes most points from the 
larger parent, and may do so even in the size of the eggs, so that 
where the cross is reversed there may be no difficulty in their 
extrusion. It was hardly to be expected that so wonderful a 
discovery as the creation of a new species could be made with- 
out trouble, and we should rather be surprised at the success 
already achieved in hatching the young of the cross at all. The 
number of combinations possible is very large, and the pains 
and care expended on improving plants, vegetables, and land 
animals, may yet succeed with fish. 
We have again this year crossed the eastern brook with the 
California mountain-trout, both ways, and have impregnated 
about eighty per cent of the eggs so used. 
