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no vegetable food whatsoever. Of the animal food, weevils 

 of several species form by far the greatest percentage, seven 

 birds having fed upon them to the exclusion of everything 

 else. Next in order of abundance are lepidopterous larvae, 

 ground beetles, spiders, and centipedes, with dipterous larvse 

 beginning to appear (Plate XVIII, fig. 2). These are the 

 forms that are found in greatest numbers in the marsh at this 

 season. With the disappearance of the ice in the spring, the 

 first insects to appear from hibernation are the weevils, which 

 occur in large numbers, but are inconspicuous because of their 

 secretive habits. Lepidopterous larvae, though numerous, 

 are even more difficult to find. In the drier portions, and 

 often on floating logs and debris, are numerous ground beetles 

 and centipedes. Other forms are exceedingly scarce. Toward 

 the latter part of April numerous dipterous (tabanid) larvae 

 appear floating on the surface, and at once form a part of the 

 Redwing's food. 



Food during the Mating Period. — This period extends from 

 the third week in April through the first week in May (April 

 21-May 7). At this time food is secured by the resident 

 birds entirely in the marsh, and is practically 100 per cent 

 animal. The vegetation in the marsh has obtained a good 

 start, and furnishes forage for large numbers of lepidopterous 

 larvae, which now take the ascendancy in the food. Dipterous 

 larvae follow a close second, with weevils, spiders, and ground 

 beetles more numerous than before, but now in the background 

 (Plate XVIII, fig. 3). 



Food during the Breeding Season. — This shows a series of 

 changes which are closely correlated with the appearance 

 and disappearance of the predominant insects in the marsh. 

 At first the lepidopterous larvae continue to predominate, but 

 frequently are superceded by dipterous larvae, which are found 

 at the surface of the water before transformation. Chauliodes 

 larvae, crawling out of the water to pupate, appear and dis- 

 appear in the food very abruptly. Rhyncophora and other 

 Coleoptera continue (Plate XIX, fig. 1). Toward the last of 

 May another decided change takes place, when the fish files 

 (Chauliodes) transform and furnish abundant and easy forage; 



