266 FUNDAMENTALS OF AGRICULTURE. 



The moth of the cotton-leaf worm, for example, lays 

 her tiny, light green eggs on the leaves of the cotton 

 plant, where they remain for four or five days. At 

 the end of this time each egg hatches into a tiny cater- 

 pillar, or larva, as it is more properly called. The 

 larva lives, at first, on the under sides of the leaves 

 and eats only the under side of the leaf. It grows rap- 

 idly, however, and, like the young grasshopper, sheds 

 its skin several times, getting larger and larger with 

 every new skin. Finally, after fifteen to twenty days, 

 the larvae become full grown, and then each one rolls 

 the edge of a leaf, and inside of this spins a thin cov- 

 ering of silken threads. The covering of silk and leaf 

 is called a cocoon. The larva, inside of the cocoon, 

 soon changes to an object known as a pupa. The pupa 

 lies quiet within its cocoon, eats nothing, and, after 

 some days, its skin splits open along the back of the 

 thorax, and the full-grown moth crawls out, dries her 

 wings, and flies away. This moth does not grow any 

 more. Neither do little flies, beetles, bees, or butter- 

 flies grow into large flies, beetles, bees, or butterflies. 

 After an insect once gets fully developed wings it does 

 not grow any more. 



EXERCISE. Catch a grasshopper, house-fly, and squash-bug, and 

 count their legs. Find a common house spider and see if it has six 

 or more legs. Observe the body of a grasshopper carefully, and see 

 how many parts to the body. What are these parts called? 



Find out how many wings a grasshopper and a fly have. Catch 

 some ants and see how many wings they have. Examine the eyes 

 and antennae of a grasshopper with a hand lens. Catch a dragon-fly 

 and look at its large eyes. Notice the black jaws of the grasshopper. 

 Put it in a glass jar or a lantern globe with thin muslin tied over the 

 top and watch its movements. Perhaps the grasshopper could be 

 induced to eat some fresh grass blades. 



Bring in some harlequin cabbage-bugs and put them on a small 

 mustard plant in a pot. Put a lantern globe, with thin muslin tied 

 over the top, over the plant and watch the bugs lay their eggs and 

 when the eggs hatch watch the young bugs grow from day to day. 

 Try to watch the life history of some potato beetles in the same way, 

 using potato plants instead of mustard. 



