VERTEBRATES 139 



Birds and Migration 



To illustrate Distribution 



Work in tlie Laboratory 

 Materials. 



Bird skins or mounted birds, at least one representative of 

 each order and, better still, of each family of the birds 

 which pass through or remain in your neighborhood ; speci- 

 mens in a museum may also be used. Some guide to the 

 identification of birds, as Walter's " Wild Birds in City 

 Parks" or Reed's "Bird Guide." A good diagram of a 

 bird. 



Directions. 



Your object here is to familiarize yourself with the ap- 

 pearance of birds of different types, and with the terms 

 used in describing them. Study first a diagram of a bird 

 and learn the terms and their applications. 



An important item in the description of a bird is its 

 length. This is obtained by measuring from the tip of 

 the beak, over the curve of the head, to the end of the tail. 

 This measures a curved line and gives a greater length for 

 a bird than the straight line you would naturally estimate. 

 Train your eye by watching house sparrows ( so-called 

 English sparrows ) and fixing their length as a unit. They 

 are called six inches long, and in the field other birds may 

 be measured by them. The robin is ten inches long, and 

 may be used to measure the larger birds. 



In describing the colors of birds, great discussions often 

 arise because pupils do not use terms correctly. Consult 

 Chapman's " Birds of Eastern North America " for a color 

 key or chart, and train yourself to observe colors carefully 

 and name them correctly. You will find more colors among 



