200 T. C. STEPHENS 



many as four young were usually fed at each visit. Similar 

 testimony is given by Airs. Miller (15, p. 18), by Baskett (13, 

 p. 110), and by Burns (14, p. 54). 



Passing on to the Macrochires we find that a considerable 

 number of observations have been recorded. 



In 1890 Mr. Brewster (16) described very vividly the feeding 

 of the young of Hummingbirds in the following words : "Alighting 

 on the edge of the nest, her tail pressed firmly against its outer 

 side in the manner of a woodpecker, her body erect, she would 

 first look nervously around, then thrust at least three-fourths 

 of the total length of her bill down between the upraised open 

 mandibles of the young bird. Next she would shake her head 

 violently as if disgorging something; then, with their bills glued 

 tightly together, both birds would remain, for the space of 

 several seconds, perfectly immovable save for a slight, rapid, 

 pulsating or quivering motion of the mother's throat. The 

 actual contact of the bills lasted once for four seconds, once 

 for six seconds, and twice for eleven seconds, the time being 

 taken by a stop watch." ..." The close and prolonged con- 

 tact of the bills, the shaking of the mother's head, the subsequent 

 quivering of the mother's, and, above all, the fact that after 

 sitting on the nest for nearly an hour, she fed the young a second 

 time without once leaving the tree in the interim, convinced 

 me that the method of feeding was by regurgitation." 



This testimony is confirmed by Shoemaker (17), for the same 

 species, who says: ' Very soon the mother bird appeared, and 

 after a wary approach, alighted upon the edge of the nest and 

 thrust her bill far down the throat of the young bird. I could 

 see her throat move as she regurgitated the food. She left 

 her bill in the little one's throat for about six seconds." 



Such direct testimony cannot well be questioned without a 

 careful re-examination of the circumstances. It should be borne 

 in mind, however, that the length of the bill in the Trochilidae 

 is a factor which must be taken into account. Even if the food, 

 which probably consists of insects, were held in the mouth, or 

 buccal cavity, we might suppose that some muscular action 

 would be necessary to force it out along the mandibular tube 

 and into the throat of the young bird. In Mr. Brewster's 

 account it does not add to the proof that the parent did not 

 leave the tree between feedings; since it might easily be assumed 

 that the tree abounded in food material, i. e., insects. 



