370 



American Fisheries Society 



were eaten. Although the very young bass is a specialized 

 feeder at first, feeding almost entirely upon entomostracans, 

 it soon becomes a generalized feeder, and up to 45 mm. feeds 

 upon an average of twelve different kinds of food. The 14 

 bass examined above 45 mm. show a gradual restriction in 

 the kinds of food eaten. 



As to the number of stages in which each of the seven 

 most important kinds of food occurred, it is noted that cope- 

 pods and mayfly nymphs were found in the first seven stages 

 of bass from 8^-45 mm. Cladocera were in 8 stages from 

 8)^-50 mm., midge pupae in 9 stages from 8^-55 mm., adult 

 insects and midge larvae in 10 stages from 8^-60 mm., and 

 fish all stages from 8j5^-65 mm. This shows that in all stages 

 between 8^ and 45 mm., bass ate the seven important kinds 

 of food, a fact which indicates that the bass at least between 

 these lengths is a versatile feeder. 



The following table gives the total list of all the materials 

 found in the stomach contents of the 313 bass examined: 



Materials Found in Stomach Contents of 313 Bass Examined 



Order of 

 importance. 



13 



15 

 i6 

 17 



Kind of food. 



Copepods 



Cladocera 



Midge pupje 



Adult insects 



Midge larvae 



Fish 



Mayfly nymphs 



Caddis pupae 



Insect cases 



Ostracods 



Vegetation 



Caddis larvae 



Copepod eggs 



Mayfly eggs 



Crayfish 



Amphipods 



Statoblasts of Plumatella princeps. 



Nauplii 



Mites 



Naid worms 



Coleopterous larvae 



Damselfly nymph 



No. of fish. 



193 



125 



86 

 78 

 62 

 S6 

 38 



Percentage. 



