CLIFF-DWELLERS 31 



the top of the chif, showing absolute familiarity 

 with her mountain home. 



The most beautiful and far the most diminutive 

 of all the cliff-dwellers are certain varieties of 

 humming-birds. They appear most abundant in 

 the mountainous regions of South America, espe- 

 cially in the high Andes, where there are hundreds 

 of different species. Here, if one is especially 

 lucky, he may occasionally find a nest attached to 

 the side of a high cliff, or overhanging rock. The 

 nests are marvels of beauty and wonder. They are 

 usually cup-shaped, and formed of plant down 

 woven together by silver spider's webs. The out- 

 side of the nests is covered with lichens, mosses, 

 and sometimes with dried flowers or feathers. 



Oven-birds are the aristocrats among the cliff- 

 dwellers, and are not satisfied with one chamber, 

 but build two in the clay not unlike ovens — hence 

 the name. These are common sights in South 

 America. Like their friends, the swallows, they 

 sometimes convert a nest into a sepulchre by clos- 

 ing up the entrance when a bird has died. It some- 

 times happens that an underground city, in case of 

 an epidemic among the inhabitants, becomes a 

 cemetery 1 



A cousin of the oven-bird, which closely resem- 

 bles this interesting home-maker in the reddish tint 



