352 Hafidbook of Nature-Study 



7. How do the nuthatches, downy woodpeckers and chickadees help 

 us in getting rid of the codHng moth? 



8. Write an essay on the hfe history of the codHng moth, the damage 

 done by it, and the best methods of keeping it in check. 



References— The foUowing bulletins from the U. S. Dept. of Agricul- 

 ture; Farmers' Bulletin 247, "The Control of the Codling Moth and 

 Apple Scab;" Bulletin 35, New Series, Bureau of Entomology, "Report 

 on the Codling Moth Investigations," price 10 cents; Bulletin 41, "The 

 Codling Moth," 105 pages, 15 cents, by Special Field Agent, C. B. Simp- 

 son; Bulletin 68, Part VII, "Demonstration Spraying for the Codling 

 Moth," price 5 cents. The Spraying of Plants, Lodeman, Macmillan 

 Company; Economic Entomology, Smith. 



LEAF-MINERS 



Teacher's Story 



"And there's never a leaf nor a blade too mean 

 To be some happy creature's palace". 



— Lowell. 



rAY not Lowell have had in mind, when he wrote 



these lines, the canny little creatures which 



find sustenance for their complete growth 



between the upper and lower surfaces of a leaf, 



which seems to us as thin as a sheet of paper. 



To most children, it seems quite incredible 



that there is anything between the upper and 



lower surfaces of a leaf, and this lesson should 



hinge on the fact that in every leaf, however 



thin, there are rows of cells containing the 



living substance of the leaf, with a wall above 



and a wall below to protect them. Some of the smaller insects have 



discovered this hidden treasure, which they mine while safely protected 



from sight, and thus make strange figures upon the leaves. 



Among the most familiar of these are the serpentine mines, so called 

 because the figure formed by the eating out of the green pulp of the 

 leaf, curves like a serpent. These mines are made by the caterpillars 

 of tiny moths, which have long fringes upon the hind wings. The life 

 story of such a moth is as follows: The little moth, whose expanded 

 wings measure scarcely a quarter of an inch across, lays an egg on the 

 leaf; from this, there hatches a tiny caterpillar that soon eats its way 

 into the midst of the leaf. In shape, the caterpillar is somewhat "square 

 built," being rather stocky and wide for its length; it feeds upon the 

 juicy tissues of the leaf and divides, as it goes, the upper from the lower 

 surface of the leaf; and it teaches us, if we choose to look, that 

 these outer walls of the leaf are thin, colorless, and paper-like. We can 

 trace the whole life history and wanderings of the little creature, from 

 the time when, as small as a pin point, it began to feed, until it 

 t.Xained its full growth. As it increased in size, its appetite grew larger 

 also, and these two forces working together naturally enlarged its house. 

 When finally the little miner gets its growth, it makes a rather larger 

 and more v.?mniodious room at the end of its mine, which to us looks like 



