HUMMING BIRDS. 
former, while it hovers on the wing, inserts its at- 
tenuated bill, and with protruded tongue extracts its 
food from the honeyed cells of pendent tubular flowers. 
The one pursues, on ever-active wing, the ranging 
insect that, with bolder flight, appears to seek a rarer 
atmosphere in the loftier regions of the firmament ; 
the other seeks the more hidden pest that delights to 
fatten, all unseen, on the nectar juice caverned within 
the calyx of the flower. The fitness of the structure 
of each bird to its peculiar functions and appointed 
occupation is wonderful and striking. The Humming 
Birds could no more exist in a climate where there 
was not a constant succession of flowers to harbour 
and nourish their prey, than the Swift could support 
its existence were no insects to people the air. 
The tongue of the Humming Bird, like that of the 
AVoodpecker and other scansorial, insectivorous birds, 
is retractile, and capable of being darted out with 
considerable force, by means of an apparatus similar 
to that of the AV^oodpecker. It is composed, according 
to Brisson and Lesson, of two muscular tubes, joined 
together through the greater part of their length, 
expanding towards the tips into a spoon-like form, 
and terminating in a sharp point. The food, which 
is procured on the tip of the tongue, is immediately 
conveyed to the opening of the oesophagus by the 
contractility of the tubes. 
These birds do not alight upon the ground, nor 
have they any other use for their feet than to 
support themselves on a perch for the purpose of 
repose; the foot is therefore simply a perching foot, 
very small and slender; the claws being rather large 
