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BULLETIN OF WISCONSIN NATURAL HISTORY SOCIETY. VOL. 2. NO. 1. 
its food. This theory is somewhat conjectural but to my mind 
seems reasonable. The fish elevates its paddle above the water 
and swims into the water plant, manipulating and guiding the 
water plant into its mouth ; this would cause a current of water 
containing the food to pass out at the gill openings, while the gill- 
rakes would catch and hold the food. The eyes are admirably 
placed to see and control the movements of the fish. After a 
proper amount of confervae is thus caught the long gill-cover and 
mouth are closed, a compression of the cavity back of the gill- 
rakes would force the water forward and out of the blow holes 
and thus release the water plant from the gill-rakes, and a further 
compression of the mouth w^ould press out the remaining water 
and leave the food in a fit condition to be swallowed without an 
undue amount of water. I once saw this fish swimming with Its 
paddle raised above the surface of the water but had no con- 
ception at that time that it was collecting food, in fact did not 
know what it subsisted upon. Fishermen have told me that they 
have seen worms in their stomachs mixed with confervae, but I 
am of the opinion the fish is a vegetarian, as I know they have 
parasitic worms in their stomachs, of which I will say more later 
on. I thought if they are vegetarians that they must hybernate 
in the winter ; as there is then no vegetation for them to live upon. 
Acting upon this impression I visited the fishermen drawing seins 
under the ice. I opened the stomachs of a number of the fishes. The 
walls of the stomachs were thick and contracted, the cavity was very 
small and in no instance was there found a particle of food in 
them, only a little yellowish fluid and sometimes a lively knot of 
parasitic worms that seemed greatly disturbed at being exposed 
to the cold atmosphere. This fish while lying in the muddy 
bottom in a torpid state during the winter is often attacked by 
lampreys, sometimes having life literally sucked out of them or so 
nearly so as not to have vitality enough to recuperate when re- 
leased from their icy prison. I have seen many of them lying on 
the shores in the spring with their bodies emaciated and covered 
by wounds made by the lampreys. I have often seen these fish 
after the water became warm jump out of the water and come 
down on. their sides with a splash, probably to rid themselves of 
lampreys. There is one very remarkable fact that no one has 
ever seen, a very small fish of this species, at least this is true as 
far as any information I have been able to obtain. I have a 
standing offer of $5.00 to any one who will bring me one not over 
six inches long, thus far without any response. 
