HABITAT 
83 
69. Frogs. — There are several kinds of frogs, one of 
which, the leopard frog, is found generally distributed 
throughout the United States. It can be recognized by the 
presence, on the dorsal surface, of many brownish or green¬ 
ish spots, edged with white, which help the frog to escape 
the notice of his enemies as he squats among the water weeds. 
These colors form rather definite bands on the hind legs, 
though there is much variation. The general form of the 
body, the shape of the head, and the long hind legs adapted 
for jumping are much 
the same in all frogs. 
LABORATORY STUDY 
Compare the general shape 
of fish and frog. How do the 
colors differ? Show how the 
legs and feet are adapted to 
the way the frog lives. Is 
the frog sensitive to touch in 
various parts of the body? 
Examine the eyes. Open the 
mouth and see that the frog 
can draw in its eyes. The ear membrane is on the side of the head back 
of the eyes. Pass a probe through the ear membrane of a dead frog 
and see where it comes out in the mouth. This is the opening of the 
Eustachian tube. How far can the living frog see ? Notice the method 
of breathing. See the throat move up and down. Hold the frog under 
the water and gently rub its sides. It will usually croak. Thus we 
can prove that the frog is able to make the air travel from his lungs to 
his mouth and back again while under water. 
70. Habitat. — Frogs are seldom found far from some 
pond or stream on the bank of which they are usually seen. 
When disturbed, they jump into the water, swim to the 
bottom, stir up the mud, and quietly come to rest a short 
distance from the place where they entered. As the nights 
in the fall grow cool, frogs make ready to spend the winter 
in a state of inactivity. During the warmer part of the day 
