USE OF PLANTS TO MAN 



367 



ANIMALS REPORTED FOR 1914 



Milk cows 20,737,000 Value per head $53.94 



Other cattle .. 35,855, 3i-i3 



Swine 58,933,000 



Sheep 49,719,000 



Horses 20,962,000 



Silk exported from Japan during the year 1912 23,413,000 pounds 



QUESTIONS AND EXERCISES 



1. What is the historical origin of the principal plants used for food? 



2. What commercial products are made of wheat, rye, oats, 

 cotton, potatoes, and flax? 



3. Examine various kinds of rope and determine the kind of 

 material of which each is made. 



4. Make a list of the plants of which paper is made. Which ones 

 have you seen? 



