Marvels of the Universe 1063 
pointed, like the wings of the Swifts (with which family the Humming-birds are closely allied ; in 
fact, they are little more than gorgeous, marvellously developed, flower-haunting Swifts). Unlike 
most other birds, the secondary quills are reduced to only six or seven in number as against ten 
primaries. 
The breast-bone is enormously developed in its keel, in order to furnish a strong base for the 
wing muscles which are intended to keep these narrow wings in a continual vibratory motion, so 
that when the bird hovers before a flower the whirring wings are quite invisible to the spectator, 
or, at any rate, only show a vague blur of grey. By this vibrating motion the bird is able to poise 
itself for quite a length of time before the object it is examining, and the whole of the flight recalls that 
of insects rather than of birds with its whirring and rapid swoops. In young birds the beak is quite 
short and with a wide gape, but in the adult is always long and sometimes is developed to a length 
more extravagant and disproportionate than is met with anywhere else in the Bird class. “For 
instance, in the Swordbill Humming-bird the nearly straight beak (curved slightly upwards) is over 
four inches long ; and in the female more than four and a half inches, or half an inch longer than 
in the male. The total length of the bird’s body is eight and a half inches. Other Humming-birds 
develop one or more pairs of feathers on their tails to an extravagant degree. Remarkable amongst 
these is the Racquet-tailed Humming-bird, in which the second pair of tail feathers are long and 
wiry and their tips expanded into large racquet-shaped terminations. The beautiful “ Doctor” 
Humming-bird of Jamaica also develops a second pair of its tail feathers to an extravagant length, 
and these are scalloped along the outer edge. 
Others, again, have their tail feathers arranged in two long “ ladders,” or in other quaint 
shapes, illustrated in the accompanying photographs. Some species here illustrated develop 
extraordinary ruffs and frills about the neck, crests on the top of the head, tufts behind the 
ear, pointed beards of feathers, or other exaggerated gorgets, or puffs of white down round the 
Pee 
By permission of] [Six H. H. Johnston, G.C.M.G. 
HUMMING-BIRDS. 
Long-tailed Humming-birds of several species: Cynanthus, Cometes and Lesbia. 
