THE FEEDING OF NESTLING BIRDS 203 



that we are unable to judge what the author's conception of 

 the regurgitative process is. 



Miss Stanwood (23) incidentally states that the Olive-backed 

 Thrush feeds by regurgitation. McAtee (24) states that Gros- 

 beaks have been observed to feed the young by regurgitation; 

 the same author elsewhere (25, p. 421; and 26, p. 342) takes 

 very positive ground in favor of regurgitation, especially in 

 the Fringillidae, but without offering any evidence. 



We may now consider the negative testimony. Jones (27, 

 p. 42) states that regurgitative feeding is never practiced by 

 the Common Tern {Sterna hirundo). 



Judd, in a very excellent account of the food of nestling birds 

 (28, p. 412), while not explicitly discussing regurgitation, says 

 that the first meal of the nestlings of the crow blackbird often 

 consists of plump spiders of soft texture. Likewise, on page 

 425, the same author says that the first meal of the Crow 

 usually is a young grasshopper, a plump spider, or a soft cutworm. 



Jones (29, p. 69) reports the observations made by his students 

 at the nestside of the Field Sparrow, the Song Sparrow, and 

 the House Wren. He says: " There was no evidence that any 

 of these birds fed by regurgitation. In the case of the sparrows 

 this was clearly proved, but what might have happened in the 

 case of the wrens can only be surmised. At any rate, the food 

 was uniformly brought dangling from the bill and was not 

 swallowed before being delivered to the nestlings. This was 

 the case with the first feedings of both the Song Sparrows and 

 the House Wrens." 



Bigglestone (30) made a careful study of the nest life of the 

 Yellow Warbler. All of the young were under observation 

 within a few hours after hatching; but the last egg was under 

 observation during hatching, and from that time onward the 

 young bird was under constant observation till it left the nest. 

 No regurgitation was observed, although this was one of the 

 chief objects of the entire study. 



A similar study was made of the Catbird by Gabrielson (31), 

 in which two of the nestlings were under observation from the 

 moment of hatching onward. Here also nothing suggestive 

 of regurgitative feeding occurred. 



During the summer of 1914 two similar nest studies were 

 completed. The first, which has not yet been published, was 



