120 



FIRST LESSONS IN ZOOLOGY. 



In the butterfly, as in the house-fly, it will be seen that 

 the front edge of the fore-wings is strengthened by two 

 veins, one of which has three branches running parallel with 

 the edge. As the weight or pressure of the air while making 

 the stroke is borne chiefly by the front of the wing, it needs 

 these rods to strengthen it. 



The scales of a butterfly's wing are curious objects for 

 study. They differ much in shape on different parts of the 

 body. On the wing of the Cecropia moth the hairs of the 

 body and base of the wing are seen to pass into broad scales 

 represented in Fig. 131. They are attached to the wing 



FIG. 131. Arrangements of the scales 

 on a moth's wing. (Magnified.) 



FIG. 132. o, scent scales; 6, ordinary 

 scale of Lycsena butterfly. (Highly 

 magnified.) 



and laid partially over one another like the tiles on a roof, 

 being inserted in irregular rows. 



The legs are rather slender, and in general like those of 

 the house-fly. 



The hind body is composed of eight distinct segments, 

 with rudiments of a ninth and tenth. 



Nothing is more interesting or instructive to the be- 

 ginner in entomology than to rear caterpillars, to see them 

 change into chrysalids, and finally emerge as butterflies or 

 moths. There are always plenty of caterpillars to be found, 

 and many of them can be easily reared in either a tumbler 

 or a roomy tin box, or in a well-appointed vivarium. 



The caterpillar or larva of the Turnns butterfly may be 

 found on the apple or birch and other trees. In July the 

 butterfly lays a nearly round egg upon the leaf, and by the 



