ws

ft

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 vertebra 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 1-2666th by 1-4000th 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—P/aéthornithine
and Trochilne ; 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.
Ido 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 Trochilide 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