INTRODUCTION. xxxv 



and destitute of indentation or fissure ; the ridges to which the pectoral muscles have their attachment large 

 and prominent, the horizontal portion much narrowed anteriorly, consequently the junctions of the cora- 

 coids are very near together. 



''Pelvis short, very broad; os pubis long, curved upwards at the extremities, projecting far downwards, 

 and posteriorly beyond the termination of the caudal vertebrae ; the ischiatic foramen small and linear ; 

 femora placed far backwards ; coracoids short, very strong, their extremities much diverging ; os furcatum 

 short, slightly arched near the extremities of the rami, which are far apart, furnished with only a small 

 process on its approach to the sternum ; scapula flattened, long, broadest near the extremity ; humerus, 

 radius, and ulna short, the metacarpal bones longer than either, the former furnished with ridges much 

 elevated for the attachment of the pectoral muscles ; caudal and dorsal vertebrae with the transverse processes 

 long and expanded; cranium of moderate strength, the occipital portion indented with two furrows, which 

 pass over the vertex, and in which the hyoids lie; orbits large, divided by a complete bony septum; the 

 lacrymal bones large, causing an expansion of the bill near the nostrils. 



"Number of cervical vertebrae 10, dorsal 6, sacral 9, caudal 5 ; total 30, 



" Number of true ribs 5, false 4 ; total 9." 



Dr. Davy states that the blood-corpuscles of a recently-killed Humming-Bird, examined by him in 

 Barbadoes, "were beautifully definite, regular and uniform. The disk very thin, perfectly flat ; the nucleus 

 slightly raised: and the two corresponding in outline. The corpuscles l-2666th by l-4000th of an inch, 

 the long diameter of the nucleus very nearly 1 -4000th. The blood was small in quantity, as I apprehend 

 is the blood of birds generally, but not deficient in red corpuscles, I have found its temperature to be about 

 105 degrees." 



I have found it impossible to divide the Humming-Birds into more than two subfamilies — Phaethornithince 

 and TrochilincB ; for I find no such well-marked divisions among them as will enable me so to do : neither 

 can I arrange them in anything like a continuous series ; so many gaps occur here and there, that one is 

 almost led to the belief that many forms have either died out or have not yet been discovered ; consequently 

 I am unable to commence with any one genus and arrange the remainder in accordance with their affinity. 

 Whenever I have observed an apparent relationship between two or more genera, they have been placed in 

 contiguity ; and the species which appear to be allied to each other are arranged in continuous succession, 

 I do not consider one species more typical than another ; all are equally and beautifully adapted for the 

 purposes they are intended to perform. 



The following Synopsis will be found to contain a general view of the subject, and, as it also comprises 

 many new synonyms and the additional information I have been able to obtain during the progress of the 

 work, should always be consulted. 



I shall now give the general characters by which the Trochilidae are distinguished : — 



Body small ; sternum very deep ; bill subulate, and generally longer than the head, straight, arched, or 

 upcurved; tongue composed of two lengthened cylindrical united tubes, capable of great protrusion, and 

 bifid at the tip ; nostrils basal, linear, and covered by an operculum ; wings lengthened, pointed, the first 



