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was so long delayed before reaching Dr. Gurley of the 
U. S. Fish Commission, as to be, in most cases, in an 
advanced state of decomposition and unserviceable for 
examination. 
Awhile back I stated that the hard, shot-like eggs and 
accompanying fluid were the cause of the imperfect 
impregnation; but if Prof. Riley is correct, they are but 
an effect and the true cause is yet deeper. A study of 
these parasites with a view of their possible elimination 
opens a field which but few if any, fishculturists are pre- 
pared to tread. If further investigation confirms the 
impression that these parasites are present, and that to 
their presence is due the loss of one-half of the possible 
efficiency of our work with the z7zdews, we have a serious 
and delicate problem; one which probably only the skilled 
bacteriologist can handle. 
Dr. Gurley has happily suggested that a simple, though 
heroic, cure may be found in the progressive elimination 
of those females producing abnormal eggs. The only 
practical solution may yet be found to lie in this direc- 
tion. In the meantime, it would be of value if any of 
our spawn takers could positively state that the female 
rainbow trout which yield normal eggs in one season do 
not yield the abnormal, hard eggs in subsequent seasons. 
The converse of this proposition would be of equal value. 
It has been suggested as a possible solution of this 
difficulty, that it arises from inflammation of the ovaries, 
established by improper and rough handling at the time 
of artificial spawning. From my own experience I can 
state that, though this suggestion may be true in some 
isolated cases, it is scarcely applicable to the case in 
general. 
At the Neosho Station during the season of 1891-92 
we spawned one thousand twenty months old zrzdeus. 
Many of the females, when handled for the very first time, 
readily gave down these hard, shot-like eggs without the 
least pressure, showing conclusively to my mind, at least 
