Lake Maxinkuckee, Physical and Biological Survey 293 



willing to seize the tempting morsel and bring disgust to the angler 

 who, after a hard fight, was looking for something much better. 

 Again it must be remembered that the fish just enumerated were 

 examined during the summer season when their other food is es- 

 pecially abundant. They could be expected therefore, to yield only 

 minimum returns in the line of fish food. 



In the winter, on the other hand, when the plankton, frogs, 

 crawfish, mollusks, and algse are less numerous, the proportion of 

 fish food probably increases. And it would not be surprising to 

 find even the crappie and bluegill eating darters and minnows 

 then. There is much reflection in the thought that not only is a 

 minnow the one bait available for fishing through the ice, but in 

 all probability it is the best that could be offered. Necessity and 

 choice go hand in hand for once. 



In the second place, the minnows themselves feed almost en- 

 tirely upon plankton and insect larvae, and hence an abundance of 

 these foods is requisite to keep up the supply. Fortunately the 

 lake is very rich in just these creatures, and although the swarms 

 of may-flies, gnats and other dipters may occasion the angler some 

 inconvenience at times, he has but to remember how essential they 

 are to the life of the fish he is endeavoring to secure. 



Species of fish studied:* In discussing the food and parasites 

 as here recorded it will be better to take up the different kinds 

 separately, considering their relative importance and abundance, 

 and proposing such recommendations as have been suggested dur- 

 ing the progress of the work. 



1. Dogfish ; bowfin. Amia calva. 



Only six specimens were examined, in whose stomachs were 

 found chiefly crawfish and minnows, with the remains of other 

 small fishes, mollusks and algje. Each of the six fishes contained 

 internal parasites, trematodes in the mouth and throat, and ces- 

 todes and Acanthocephali in the stomach and intestine. There was 

 also a trematode (Azygia tereticolle) in the gills of four of the 

 specimens. On the outside of the body one fish yielded Argulus 

 americanus, and three gave two different species of leeches. 



The dogfish in Lake Maxinkuckee seem to be unusually free 

 from tapeworms. All those examined elsewhere are invariably 

 found loaded down with masses of tapeworms, the penalty of their 

 voracious and carnivorous habits, but here they seem to have es- 

 caped. 



* Considerable additional data regarding the food of Maxinkuckee fishes will be found in 

 the chapter on Fishes (pp. 306-451). 



