282 REPORT OF NATIONAL MUSEUM, 1890. 



A nest of Boricha enicura found by Mr. Salvia in Guatemala further 

 illustrates the remarkable reasoning faculties of Humming Birds. It 

 "was most curiously placed in the cup-shaped top of a fruit of the 

 Nopal [Cactus cochinellifera), the fastenings being dexterously wound 

 round the clustering prickles and thus retaining the whole structure 

 firmly in its place." It was remarkably shallow, so much so, in fact, 

 that had it not contained two eggs Mr. Salvin " would have pronounced 

 it far from complete;" and he adds that "it may be that, being based on 

 a firm foundation (one not nearly so liable to oscillation by the wind), 

 the bird had found that a greater depth was not necessary to keep the 

 eggs from falling out. Had she placed her nest on a slender twig, as 

 usual, the case might have been different." (The Ibis, vol. 11, p. 264.) 



An extraordinary and most convincing exhibition of a Humming 

 Bird's intelligence once came under the personal observation of tbe 

 writer. A nest of the Broad- tailed Humming Bird [Selasphorus platy- 

 cercus) had been built upon a dead twig of an aspen bush, some 3 

 feet from the ground ; the dry atmosphere had caused the bark of the 

 twig to crack, making a transverse fissure on each side of the nest, the 

 wood at the same time shrinking so that the cylinder-like section of 

 bark inclosed it loosely. After the eggs were laid something had 

 caused the section of bark to turn, so that the nest hung inverted on 

 the under side of the branch, of course spilling out the eggs. When 

 found by the writer the nest was in this position, with the fragments 

 of the eggs lying on the ground beneath it; but immediately above the 

 original nest was a new one, very much smaller than the first, contain- 

 ing two fresh eggs. Evidently the owners knew that by building a 

 much smaller nest above the old one (which was rather a bulky one for 

 the species) the greater weight of the latter would keep the former in 

 position and thus prevent a recurrence of the accident. 



Mr. C. H. Holden was " struck with the wisdom" of this same species 

 in the matter of nest-building, a nest which he found in the Black Hills 

 of Wyoming having been built upon one of the lower branches of a tree 

 that had fallen across a brook, in such a way that the trunk of the tree 

 effectually shielded it from the rain and sun. 



Other Humming Birds, again, build their nests of materials corre- 

 sponding exactly in color with the branches to which they are attached, 

 this being frequently the case with the Calliope Humming Bird (Stel- 

 lula calliope) of the western United States, which often builds its nest 

 upon a dead pine branch, upon or near a cone of similar size and color, 

 as shown on plates n and in, while some of the tropical species, of the 

 genus Phaethornis, attach theirs to the tip of a long pendant leaf of a 

 palm, as shown on plates IV and V. 



NESTS AND EGGS. 



Humming Birds' nests are among the most beautiful examples of bird 

 architecture. They are usually compactly felted structures, of various 

 forms, the cup-shaped or turban-shaped, however, prevailing, the ma- 



