666 Handbook of Nature-Study 



Observations on the growth of corn Work for the Summer Vacation 



17. How does the corn look when it first conies up? How many 

 leaves are there in the pointed roll which first appears above the ground ? 

 How long before the central stalk appears? 



1 8. When do the tassels first appear? What kind of flowers are the 

 corn tassels ? Describe the anthers . How many on each flower ? Where 

 do the anthers open to discharge their pollen ? 



19. How large are the ears when the pollen is being shed? Study an 

 ear of corn at this period. Note that the kernel is the ovule, the silk is 

 attached to it and is the long style extending out beyond the husks. Note 

 that the tip, or stigma is branched. 



20. What carries the pollen for the corn plant? If you have rows of 

 popcorn and sweet corn or of sweet corn and field corn next to each other 

 why is it that the ears will show a mixture of both kinds? 



EXPERIMENT I 



Compare the growth of the corn plant with that of the pigweed. 

 When the corn-stalk first appears above ground, tie two strings upon it, 

 one just above a joint and one below it. Tie two strings the same dis- 

 tance apart on the stem of a pigweed. Measure carefully the distance 

 between these two strings on the two plants. Two weeks later measure 

 the distance between the strings again. What is the result ? 



EXPERIMENT 2 



Measure the distance between two of the nodes or joints near the tip of 

 a certain corn-stalk. Two weeks later measure this distance again and 

 compare the two. 



EXPERIMENT 3 



When a stalk of corn is still green in August, bend it down and place a 

 stick across it at about half its length. Describe how it tries to lift itself 

 to an erect attitude after two or three weeks. Cut lengthwise across one 

 of the nodes, beyond the point held down by the stick, and see the wedge- 

 shaped growth within the joint which helps to raise the stalk to an upright 

 position. 



EXPERIMENT 4 



During the August drought, note that the corn leaves are rolled . Give 

 a corn plant with rolled leaves plenty of water and note what happens. 

 Why? 



THE COTTON PLANT 



Teacher's Story 



There are some plants which have made great chapters in the histories 

 of nations, and cotton is one of them. The fibre of cotton was used for 

 making clothing so long ago, that its discovery is shrouded in the myths 

 of prehistoric times. But we believe it first came into use in India, for in 

 this land we find certain laws concerning cotton which were codified 

 800 B, C.; and allusions to the fine, white raiment of the peoples of India 

 are frequent in ancient history. Cotton was introduced into Egypt from 

 India at an early date; it was in common use there 150 B. C. But not 



