INTRODUCTION, xix 



expected. The bird does not usually glide through the air with the quick darting flight of a Swallow or 

 Swift, but continues tremulously moving its wings while passing from flower to flower, or when taking a more 

 distant flight over a high tree or across a river. When poised before any object, this action is so rapidly 

 performed that it is impossible for the eye to follow each stroke, and a hazy semicircle of indistinctness on 

 each side of the bird is all that is perceptible. "The wind produced by the wings of these little birds," says 

 Mr. Salvin, " appears to be very considerable ; for I noticed that while an example of Cyanomyia cyanocephala 

 which had flown into the room was hovering over a large piece of wool, the entire surface of the wool was 

 violently agitated." Although many short intermissions of rest are taken during the day, the bird may be 

 said to live in air — an element in which it performs every kind of evolution with the utmost ease, frequently 

 rising perpendicularly, flying backward, pirouetting or dancing off', as it were, from place to place, or from 

 one part of a tree to another, sometimes descending, at others ascending; it often mounts up above 

 the towering trees, and then shoots oflf like a little meteor at a right angle ; at other times it quietly buzzes 

 away among the little flowers near the ground ; at one moment it is poised over a diminutive weed, at the 

 next it is seen at a distance of forty yards, whither it has vanished with the quickness of thought. During 

 the heat of the day the shady retreats beneath the trees are very frequently visited ; in the morning and 

 evening the sunny banks, the verandahs, and other exposed situations are more frequently resorted to. 



The foregoing remarks are from personal observation of the habits of Trochilus Coluhrk ; and I have been 

 informed by Mr. Salvin and others that a similar action characterizes most of the species. I believe, however, 

 that those members of theTrochilidse which are furnished with more ample wings, such as the species of the 

 ^tx\idY?i Aglceactis, Ramphomicron, Pterophanes^diwA /^fir/fif^o/zfif, have a very different mode of flight, move their 

 wings with diminished rapidity, and pass much more slowly through the air. Mr. Darwin, when speaking 

 of the Patagoiia gigasj says, "Like others of the family, it moves from place to place with a rapidity which 

 may be compared to that of Syrphus among Diptera, and Sphinw among Moths ; but whilst hovering over a 

 flower it flaps its wings with a very slow^ and powerful movement, totally diflferent from that vibratory one, 

 common to most of the species, which produces the humming noise. I never saw any other bird, where the 

 force of its wings appeared (as in a butterfly) so powerful in proportion to the weight of its body. When 

 hovering by a flower, its tail is constantly expanded and shut like a fan, the body being kept in a nearly 

 vertical position. This action appears to steady and support the bird, between the slow movements of its 

 wings." 



In the intervals of flight, I believe that they not only rest in the ordinary way, but even pass some time 

 in sleep; at least I found that this was the case with my living birds, and that from this state of partial 

 torpor they were not easily aroused. In the morning and evening they were far more animated than at any 

 other period of the day ; and they would even perform their buzzing evolutions round their cage, and sip 

 from their little bottle in the night-time, if a light was brought into the room. They usually sat in a moping 

 position, with the bill in a line with the body, or slightly elevated, after the manner of the Kingfishers. I 

 never saw them hang by their feet and sleep with their heads downwards — a position which I have been 

 informed is sometimes assumed by Humming-Birds. 



When we have compared the wings of Calliphlox anieihysthius with those o^ Patagona gigas, we have 

 noticed the two extremes of development in these organs ; but many intermediate forms exist, and each 

 modification has doubtless an influence on the mode and power of flight. I cannot leave the subject of the 



