THE HUMMING-BIRDS AND SWIFTS 



163 



theless, the kinship exists and much of their internal structure is very similar. As already intimated, if one 



examines the newly hatched humming-birds with their tiny bills and large mouths, or the large dull-colored 



giant hummer of the Andes, the relationship is better understood. 



There are nearly ioo species of swifts, of which about a third are found in the New World. Of these but four 



occur in the United States and Canada, and only one, the chimney swift, is ever found east of the Rocky Moun- 

 tains. This 

 bird is com- 

 monly called 

 the chimney 

 swallow and 

 indeed it re- 

 s e mb 1 e s a 

 swallow much 

 more than it 

 does a hum- 

 ming-bird, al- 

 though there 

 is no real re- 

 lationship be- 

 t w e e n the 

 two, the swal- 

 lows being 

 but modified 

 passerine or 

 p e r ch i n g 

 birds, while 

 the swifts and 

 the humming- 



LOOKING DOWN A CHIMNEY 



The fragile nest of the chimney swift with its three pure white 

 eggs is fastened to the side, fifteen feet from the top. 



HAPPY HOUSEKEEPERS CONJUGAL BLISS IN 

 A CHIMNEY 



The two chimney swifts are sitting on the nest side by side, 

 their heads close together. Since they are just the color of 

 the soot in the chimney, it is a difficult subject for the camera. 



birds form a very different 

 order. 



With few exceptions, swifts 

 are sooty black birds of rather 

 short harsh plumage, some- 

 times with white on the rump 

 or underpans, but often with 

 no marks whatever. The chim- 

 ney swift, for example, is en- 

 tirely sooty and but little lighter 

 below than above. The East 

 Indian tree swifts are excep- 

 tions in which the plumage has 

 a metallic gloss and the feath- 

 ers are quite silky. 



The most interesting thing 

 about the swifts is their meth- 

 od of nesting. The nests are 

 built of sticks, straws, feathers 

 or other material in the form of 

 a shallow saucer, cemented to- 

 gether and to the wall of the 

 cave, hollow tree, or chimney, by 

 means of the birds' saliva which 

 is specialized into a peculiar 

 glue. In one group of swifts 

 inhabiting the islands off the 

 east coast of Asia, the nests are 

 made entirely of this saliva. It 

 is from these nests that the 



CROWDED FROM THE NEST 



Chimney swifts lay but three eggs, but the nest is so small 

 that the young soon outgrow it and have to climb out and 

 cling to the wall, propping themselves with their tails, as do 

 the woodpeckers. 



famous "birds' nest soup" is 

 made, and the birds themselves 

 are called the "esculent swifts." 

 They nest in large colonies in 

 caves and the gathering of the 

 nests is an organized industry. 

 The nests weigh about half an 

 ounce and bring as high as 

 $7 a pound and, although they 

 have been gathered from some 

 caves for over 200 years, there 

 seems to be no diminution in 

 the number of the birds. 



The nest of the chimney swift 

 is built of short twigs which the 

 birds break from the tops of 

 dead trees either with their bills 

 or feet as they swoop past with- 

 out stopping. An area in the 

 chimney or silo, as shown in 

 the illustration, is first coated 

 with the viscid saliva .so that 

 sticks will adhere to it. Others 

 are then added and coated with 

 the peculiar glue until a. little 

 saucer is constructed strong 

 enough to support the weight 

 of the bird, or even both birds, 

 for they sometimes sit on the 

 nest side by side. The nest is 



