LABORATORY WORK: BIRDS. 



The following account will apply to almost any common 

 bird. The English sparrow or the pigeon is possibly the 

 most convenient. 



EXTERNAL. 



Notice that the body presents the regions, head, neck, 

 trunk, and tail. How many paired appendages are found ? 

 What covers the body ? what the legs and feet ? 



In the head notice the beak, composed of upper and 

 lower mandibles. With what is it covered ? Is the upper 

 mandible movable ? Open the mouth ; do you find teeth ? 

 What is the shape of the tongue ? Where are the nostrils ? 

 Do they connect with the mouth ? Behind the tongue, on 

 the floor of the mouth, will be found the glottis (p. 40). 

 How many eyelids do you find ? Look at the inner corner 

 of the eye for the nictitating membrane. Pull it out 

 with the forceps. Is it like the same structure in the 

 turtle ? Hunt among the feathers for the ear-opening. 

 Are the feathers around it different from the others ? 



Extend the wing. Can you find parts corresponding to 

 arm, forearm, and hand T Are the feathers alike in all 

 parts ? * How much is the surface of the wing increased 

 by the feathers ? 



* The feathers on different parts of the wing have special names. 

 The long quills on the hand are primaries ; on the forearm, secondar- 

 ies ; and those on the arm, when they occur, are tertiaries. The short 



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