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ANIMAL ACTIVITIES. 
Where does the bird find the oil used in preening its 
feathers ? 
How does the size of a bird’s egg compare with the 
size of its body? How does the size of a frog’s egg 
compare with the size of its body ? 
Are the senses of the bird keen or dull ? Does the 
bird have the same senses as man ? 
How would you describe the song of the bird you 
are studying ? 
The Wing. What is the shape of the wing ? 
How many joints has it ? 
Do you find bones corresponding to those of your 
own arm, forearm, wrist, palm, and fingers ? Use a 
prepared skeleton of a wing. 
How many bones in arm, forearm, wrist, and palm ? 
How many fingers ? Is there a thumb ? Sketch the 
skeleton of the wing. 
Does the skeleton of a frog show a similar structure 
of the arm ? How does the arm of a turtle compare 
with the wing of a bird ? . 
Do you find feathers on the thumb ? on the hand ? 
on the forearm ? on the arm ? 
The Leg and Foot. Do you find thigh, shin, ankle, 
foot, and toes ? Where is the heel ? Sketch the 
skeleton of the leg. 
How many toes ? Do all the toes point in the same 
direction ? 
Are there feathers or scales or both on the tarsus ? 
When scales are present what is their shape ? 
Are there webs between the toes ? 
In a fresh specimen can you find the tendon which 
moves the toes ? How do the toes act in perching ? 
Feathers. Obtain some large feathers from the 
wing or tail of a pigeon or a barn-yard fowl. Notice in 
a single feather the shape as seen in outline. Do you 
make out the shaft and the vane ? Sketch a feather. 
Can you separate the parts of the vane into branches 
of the shaft (barbs) ? 
