Diseases of Fishin the Adirondacks 2 
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were taken to insure careful fixation. When the different organs 
were studied for possible larval stages, some of the snails revealed 
the presence of a large number of brownish bodies in the liver. These 
bodies are elongated and in a few instances show what I believe to be 
a pair of intestinal tubes. The action of the digestive processes in 
the stomach of the perch which breaks down the tissues of the snail 
does not have any effect on them. The body seems to be covered with 
a thick cuticle and after fixation with formalin I am unable to make 
out any cells. This might be taken by some to argue against their 
being separate organisms. As further evidence of the correctness of 
this interpretation, three flatish worms were found .7 mm. in length 
while dissecting the organs of a snail preparatory to making sections. 
The snail which contained these three worms was so macerated as a 
result of the digestive changes that the organs fell to pieces when taken 
from the shell. I feel reasonably certain that each of these worms 
contains a pair of digestive tubes, while the space between the branches 
Original by W. M. Smallwood 
Ficure 9. Later larval stage of flatworm with the intestinal tubes 
clearly defined and the intervening space packed full of round bodies 
similar to those shown in figure 8. 1.2 mm. long, .2 mm. wide. From 
snail, Amnicola limosa. Original. 
of the intestinal tract is packed full of round bodies. The color of 
these worms is identical with those found in the liver. Their reaction 
to stains is the same, so that those found in the liver impress one as 
being but a younger stage. The fact that these brown bodies do not 
occur in all of the snails and the further fact that larger specimens 
were secured suggests that I] have part of the life history of one of 
the flatworms, but which one cannot be stated at present. The crucial 
test will come when the living tissues are examined which I plan to 
do next summer. 
It is possible that the larval stages exist in the muscles of the perch. 
When the muscles of the perch are carefully examined, especially 
along the back, one frequently finds a number of small cysts. Osborne 
has given a careful description of the cysts of Clinostomum margina- 
