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at this time they occur even more abundantly in the Redwing's 

 food than do the dipterous larvae, which are still very numerous. 

 Weevils and lepidopterous larvae continue to occur, and beetles 

 of the genus Donacia begin to appear (Plate XIX, fig. 2). 

 Between the last of May and middle of June other changes 

 probably take place, such as by the transformation of caddis 

 flies and May flies, which are known to form an important item 

 in their food. About the middle of June, however, there 

 suddenly appear in the marsh great hosts of Donacia, which in 

 a few days overrun everything, and arise in swarms ahead of 

 one who walks through the sedges and burreeds. They are 

 so abundant and so readily captured by the Redwings that 

 they constitute nearly 100 per cent of its food at this season. 

 Among the few other insects taken, dipterous larvae pre- 

 dominate (Plate XIX, fig. 3). 



Food during the Molting Season. — The diet of Donacia 

 continues until the birds begin to flock and fly to the uplands 

 in July. At this time the percentage of animal food de- 

 creases to nil. With the retirement to the marsh in late August 

 for the latter part of the molting season, however, the per- 

 centage of animal food again increases, as there are but few 

 seeds available in the open marsh at this season. In it 

 weevils and lepidopterous larvae predominate, while several 

 species of Polyganum supply the greater part of the vegetable 

 food. This augmentation of the animal diet is but temporary, 

 for as soon as the Redwings begin flying to the uplands again 

 in late September, the percentage of animal food steadily 

 decreases. 



Food during the Fall Flocking. — In October, during what 

 we may call the period of fall flocking, animal food constitutes 

 but 18 per cent. At this season of the year food is secured 

 mostly from the uplands, but in the evening and morning 

 some is secured from the marsh. A study of the insects eaten 

 shows a great variety, but Donacia and Rhyncophora pre- 

 dominate. The vegetable food is very similar to that of the 

 spring, being largely the seed of the one grass, Setaria glauca, 

 with an admixture of the seeds of other grasses, ragweed, and 

 bindweed. 



