150 A-BIRDING ON A BRONCO. 



often been an eye-witness to that. One little 

 acquaintance made a nest of yellow down and 

 put it among the green oak leaves, making me 

 think that the laws of protective coloration had 

 no weight with her, but before the eggs were 

 laid she had neatly covered the yellow with 

 flakes of green lichen. I found her one day 

 sitting in the sun with the top of her head as 

 white as though she had been diving into the 

 flour barrel. Here was one of the wonderful 

 cases of ' mutual help ' in nature. The flowers 

 supply insects and honey to the hummingbirds, 

 and they, in turn, as they fly from blossom to 

 blossom probing the tubes with the long slender 

 bills that have gradually come to fit the shape 

 of the tubes, brush off the pollen of one blossom 

 to carry it on to the next, so enabling the plants 

 to perfect their flowers as they could not without 

 help. It is said that, in proportion to their 

 numbers, hummingbirds assist as much as insects 

 in the work of cross-fertilization. 



Though this little hummer that I was watch- 

 ing let me come within a few feet of her, when 

 a lizard ran under her bush she craned her neck 

 and looked over her shoulder at him with surpris- 

 ing interest. She doubtless recognized him as 

 one of her egg-eating enemies, on whose account 

 she put her nest at the tip of a twig too slender 

 to serve as a ladder. 



Another hummingbird who built across the 



