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THE FOOD OF ILLINOIS FISHES. 



By S. A. FORBES. 



But little has been written on the food of the fresh water fishes of this 

 country, and n o thing whatever, so far as I can learn, on the food of the fishes of 

 of this state. I have not found anything more elaborate than a short paper* by 

 Prof. S. I. Smith, of Yale College, on the food of a few specimens of White Fish, 

 Red Horse (^Myxostoma aareoluni), Yellow Perch and Sturgeon (Acipenser 

 rubicundus), from Lakes Superior and Erie. An itemf relating to the food of 

 the White Fish was published by Dr. Stimpson, of the Chicago Academy of 

 Sciences, in 1870, and a few scattered notes of single observations occur in 

 various papers on classification. J 



The importance of the subject, both to the scientific student and to the 

 practical fish breeder, seems to warrant more systematic work ; and a 

 methodical investigation has therefore been begun at the State Laboratory, 

 the first results of which are given in the following memoranda. 



PURPOSES OF THE INVESTIGATION. 



A thorough knowledge of this subject should contribute something to 

 our theories of distribution, since the food of those forms having appetites 

 at all discriminating must have much to do with their range. Light might 

 even be thrown upon past distribution, and the causes be suggested of ex- 

 tensive migrations. The chosen haunts of different groups within their hab- 

 itat, are probably determined largely by their gastronomic needs and pref- 

 erences. Do the wide-spread species eat similar articles throughout their range, 

 or are they wide-spread because they are omnivorous, or because their food 

 habits are more flexible than those of other fishes ? On the other hand, are 

 the narrowly limited species ever restricted by the local character of their 

 food? 



* Report of U. S. Commissioner of Fish and Fisheries, Pt. II, p. 690. 

 t American Naturalist, Sept. 1870, p. 403. 



t A paper by Dr. C. C. Abbot in the Report of the U. S. Fish Commissioner for 

 1875-6 will also repay examination. 



