FOR WAGGONER’S BIOLOGY 
49 
in each case as far as it is possible to do. Each member of the 
class may then write a brief report of the discussion. If it seems 
advisable, the best of these reports may be published in the 
school or local newspaper. 
EXERCISE 52 (Supplementary) 
THE VERTEBRATE SKELETON 
Use a skeleton or chart. If neither is available, use the illustra¬ 
tions from text books. Study the skeleton of the human; then, 
if possible, compare it with that of the fish, the frog, a reptile, a 
bird, and another mammal, such as the cat or rabbit (hare). 
I. Note the general character of each of the parts of the skele¬ 
ton — the skull, the trunk, and the limbs. What are the Uses of 
the bones in each of these parts? 
II. The Skull. What are the character and general form of 
these bones? How are they joined to one another? Where, on the 
body, are blows most likely to fall? Of what significance are the 
shape and character of the skull with regard to such blows? Note 
the bones of the face, the jaws, and the nose. How are the eyes 
protected? How is the lower jaw attached to the skull? 
III. The Trunk. Note the number, the arrangement, and the 
position of the ribs. How are the ribs attached to the breastbone? 
To the backbone? How many vertebrae make up the spinal 
column? What is the use of the spinal column? Note the projec¬ 
tions on the vertebrae. Of what use are they? Where is the spinal 
cord located? How is it protected? What is the relation of the 
spinal column to the skull? Note the “ cushions ” between the 
vertebrae. Of what value are they? By what means is the spinal 
column supported at its base? 
IV. The Limbs. What is the character of the large bones of the 
arm and of the leg? Name the three largest bones of each. What is 
the nature of the shoulder blades? How are they attached to the 
