THE IRIS OF BIRDS. 



If we look at the birds about us, we shall soon notice that 

 not all of them have the same colored eyes. Can you tell 

 the color of a dove's iris? of a crow-blackbird's? of a gray 

 parrot's ? You will find more difference among them than 

 among boys and girls with their brown, blue, and gray eyes. 

 When we begin to observe these differences, we ask certain 

 questions as : How many colors do birds' eyes have ? Is the 

 color always the same in the same kind of bird? Is it the 

 same all through the bird's life ? 



There are birds with white, blue, green, red, purple, orange, 

 yellow, and brown eyes. Black eyes are among the rarest, for 

 most of our black-eyed birds, like our black-eyed boys and 

 girls, have a dark brown iris. If you ever held an English 

 sparrow in your hand, you may have noticed what a clear 

 brown the iris is. The old pelican waddling about the park 

 has a white iris ; the puffins are blue-eyed ; cormorants are 

 green-eyed; most wild pigeons have eyes of some shade of 

 pink or purple ; while owls and herons are usually yellow-eyed, 

 and hawks are either yellow, red, or brown eyed. Nearly all 

 our small ])irds have dark brown eyes. We must remember 

 that it is only the iris which is colored ; the pupil of every 

 healthy eye is black. Notice the eyes of different animals. 

 Did you ever see a white-eyed horse ? or a blue-eyed cat ? or a 

 yellow-eyed dog ? What are the commonest colors seen in the 

 eyes of horses, dogs, and cats ? 



Naturalists think that wild birds and animals of the same 



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