Moore. — Plants in Pond Fish Culture 



149 



and cladocerans in the fairly wide range of organisms taken. The 

 prevalence of these forms in the dietary has led to a consideration 

 of the food of these organisms. The following table shows the 

 nature of the food of certain midge larvse which were conspicuous 

 in the food of the young bass. 



FOOD OF MIDGE LARVAE. 



*a = Orthocladius nivoriundus. 

 *b = Pseudochironomus sp. 

 *c = Chironomus nigricans. 



f = Source. 



My attention was directed to the study of the midge larva, 

 Orthocladius nivoriundus, because on examination of the bass 

 stomachs this larva formed a large percentage of the food supply 

 during the latter part of June and early July. The larval cases 

 were found to be very abundant in the floating algal mats of 

 Mougeotia, a delicate filamentous green alga which forms a thin 

 scum at the surface of the pond, particularly in the sheltered 

 portions, or, when very abundant, effecting a delicate drapery 

 over the erect plants with which it comes in contact. 



Two other chironomids apparently sought after by the young 

 fish belong to the genera Pseudochironomus , species undetermined, 



