254 THE REASON WHY : 



&quot; One part had the-- plumes al whyt, another hadde them al 

 redde, and the thyrde hadde them oi several colours.&quot; HALL. 



retaining for any length of time sufficient heat for the purposes 

 of incubation, unless this provision is made. 



778. Why is so small a creature as the humming-bird more 

 plumed than any other bird ? 



The probable reason is, that this brilliancy serves to attract 

 around the, humminy-bird the insects upon which it partly feeds, 

 and thus ministers to its means of sustenance : as we see that 

 moths and flies are attracted by a lighted lamp or candle, and rush 

 upon it to their own destruction. 



779. &quot; I have seen the humming-bird,&quot; says Wilson, &quot; for half-an-hour at a time, 

 darting at those little groups of insects that dance in the air in a fine summer 

 evening, retiring to an adjoining twig to rest, and renewing the attack with a 

 dexterity that sets all other fly-catchers at defiance.&quot; 



The colouring of the plumage of birds unquestionably depends upon the sun, 

 because they are gay and glossy in proportion as they are exposed to the action of 

 that luminary ; but the light of the sun must have a substance upon which it can 

 act; and it appears to act most powerfully upon the firm feather which grows 

 slowly, and, in the first instance, under cover. The colouration is an after process, 

 though an obscure one, and one upon which it does not appear easy to get more 

 information ; but it has no apparent connection with the colour oi the egg ; for the 

 bee-eaters have, in one or other of the species, all the colours of the rainbow, as 

 brilliant as in the rainbow itself, and yet the eggs are white. Whether the bright 

 colours are less sentient to the sun than the more sober hues of the birds of cold 

 climates we are unable to tell ; but the smooth surface and metallic lustre must 

 reflect the light, as well as decompose it by that refraction which shows the 

 colours ; and we find the same kinds of tint and gloss in the day-insects of sunny 

 climes, and in the birds of the same. We may therefore conclude that the 

 resplendent plumage of these birds answers as a sort of protection against the 

 ardour of the sun, just in the same manner as the half-furry clothing of the 

 northern owls protects them against the pelti:ig sleet and the driving snow, or as 

 the down upon sea-birds protects them against the action of the water.* 



780. Why are the feet of the creeper very long and 

 powerful ? 



Because by their means the bird is enabled to cling to the 

 perpendicular surface of trees, and is enabled to use its beak with 

 great effect in the obtaining of its food. 



* Paiiington s &quot; Cyclopaedia,&quot; Art., &quot; Bee-eater.&quot; 



