lOO FARM FRIENDS AND FARM FOES 



the old. They then feed again for a week or so before 

 molting for the second time. 



These processes of feeding and molting are commonly 

 continued for four or five weeks, the caterpillars eating 

 more and more of the leaves as they grow older. They, no 

 longer confine themselves to the succulent young leaves 

 and shoots. A single insect may do much damage to a 

 young tree, as it consumes a relatively large amount, of the 

 growing tissues of the plant. When full grown in the 

 caterpillar stage, the insect changes to the chrysalis, gen- 

 erally attaching itself by silken threads to the bark of a 

 twig or branch of the orange tree. The chrysalis takes on 

 the same general coloring as the surrounding bark, so that 

 it becomes decidedly inconspicuous. In a little less than 

 a fortnight it emerges as an adult butterfly. 



Like the caterpillars of the other Swallow-tail Butter- 

 flies, these Orange-dogs have curious yellowish scent organs, 

 which protrude from the upper surface just behind the 

 head. When the caterpillar is disturbed, these give forth 

 a very disagreeable odor, which is believed to serve as a 

 means of repelling birds and possibly other enemies. At 

 any rate, good observers have noticed that the insect is not 

 molested by birds, although it is known to be subject to 

 attack by various insect parasites. Each female butterfly, 

 apparently, is able to deposit four or five hundred eggs, 

 and one of the interesting ways suggested for preventing 

 the injuries of the caterpillars is to shoot the butterflies 

 upon the wing with cartridges loaded with sand or small 

 bird shot. 



Sphinx Moths 



A beautiful family of the scale-winged insects is that of 

 the Sphinx Moths or Sphingidae ; these are. commonly 



