49 
albatross both for speed and endurance. The latter seems to ily 
without the slightest effort, and never to tire. The swift is 
another e.^ample of graceful and rapid flight-the longest summer’s 
day, from dawn till dusk, seems too short to tire it -high ui) in 
the air, it looks like the birds we used to draw at school— one 
dark hue for the body, the rest all wings. The rounded wing 
indicates diminishe.l power and a more laborious style of flight. 
4 be partridge flies with great rapidity, due to the momentum im- 
parted to Its heavy body by the rapid strokes of its short powerful 
wing^, but It po.ssesses none of the airy elegance of its long-winded 
brethren and continues its flight no longer than is nece.s.sary to 
change its feeding ground or secure its safety.* 
Again, the wing of the divers is reduced to the .smallest dimen- 
sions compatible with flying at all, and is as useful for progression 
under-water as through the air-it, in fact, serves two purposes 
and in two different elements-in the air as a wing, and in the 
water as a fin. The penguins are incapable of flight, but use the 
wing with great effect in diving ; the same may be said of the 
great auk, a bird iurmerly found in the northern seas, but now 
probably extinct. As niiglit be expected, the wing of the diving 
birds is specially adapted to their mode of life; the quill feathers 
are short and stiff, and in the species just mentioned, it is reduced 
o a mere paddle to aid progression under water. The same 
gmdations may be tmeed in the land birds, from the long-win.^ed 
kite to the ivingless apterix. With the exception of those few 
which are unable to sustain themselves in the air, the divers fly 
with great velocity, the wings being worked with extreme rapidity 
by very powerful muscles, but they are possessed of very little 
facility of evolution, flying straight to and from their feeding 
* What has been said with regard to weight, and the form of the wing in 
birds, applies equally to insects. The hawk moths have very large bodies 
.roadest at the thorax, the abdomen stout but tapering, the wings are 
long, narrow, and pointed, and their flight direct and rapid almost Syond 
conception. The flight of the cabbage butterfly, with its thin, hght bl 
and lai^ge rounded wings, is feeble and uncertain in the extreml-it hi’ 
u sects recently, I was struck with the position in which the wings of oile or 
tj o huniining-bird hawk moths were set; the iiosition was prfeisely thi 
which would lie assumed for the piiniose of hoi'erin>j-& style of fliitfor 
which this beautiful insect is so celebrated. ^ 
E 
