92 THE APPLE LEAF HOPPER 



than one-half inch long, and transforms into a blackish or brownish- 

 black beetle of about the same length. 



The life history of this pest is such, evidencing apparently marvel- 

 ous instinct, that it commands our admiration. The female beetle, ac- 

 cording to Fitch, normally lays her eggs in spring or summer on a 

 green succulent twig in an angle between leaf twig and leaf stalk. This 

 action affords the young tender food of the right nature, easily obtained. 

 As the larva grows older it works into the older wood. At this time 

 the "worm" is about half grown. According to the above writer and 

 others, this larva needs moisture to go through with its transforma- 

 tions to the pupal and later to the imago stage. This evidently it could 

 not obtain if the twig remained on the tree. It therefore, proceeds to 

 cut off the twig which has afforded it a home, so that this will lie on 

 the moist earth during the autumn and winter. This is a very nice 

 operation, evidencing apparently, as stated above, remarkable instinct. 

 Fitch tells the story so nicely that we reproduce here his account : 



"Tlie worm, being about half grown, is now ready to cut the Hmb asunder. 

 But this is a most nice and critical operation, requiring much skill and calcula- 

 tion, for the limb must not break and fall while he is in the act of gnawing 

 it apart, or he will be crushed by being at the point where it bends and tears 

 asunder, or will fall from the cavity there when it breaks open and separates. 

 To -avoid such casualties, therefore, he must after severing it have time to 

 withdraw himself back into his hole in the limb and plug the opening behind 

 him before the limb breaks and falls. And -this little creature accordingly 

 appears to be so much of a philosopher as to understand the force of the winds 

 and their action upon the limbs of the tree, so that he can bring them into 

 his service. He accordingly severs the limb so far that it will remain in its 

 position until a strong gust of wind strikes it, whereupon it will break off and 

 fall. 



"But the most astonishing part of this feat remains to be noticed. The 

 limb which he cuts off is sometimes only a foot in length and is consequently 

 quite light; sometimes ten feet long, loaded with leaves, and very heavy. A 

 man by carefully inspecting the length of the limb, the size of its branches, and 

 the amount of foliage growing upon them could judge how far it should be 

 severed to insure its being afterwards broken by the winds. But this worm 

 is imprisoned in a dark cell only an inch or two long in the interior of the 

 limb. How is it possible for this creature, therefore, to know the length and 

 weight of the limb and how far it should be cut asunder? A man, moreover, 

 on cutting a number of limbs of different lengths so far that they will be 

 broken by the winds, will find that he has often miscalculated, and that several 

 of the limbs do not break off as he designed they should. This little worm, 

 however, never makes a mistake of this kind. If the limb be short it severs 

 all the woody fibers, leaving it hanging only by the outer bark. If it be longer 

 a few of the woody fibers on its upper side are left uncut in addition to the 

 bark. If it be very long and heavy not more than three-fourths of the wood 

 will be severed. With such consummate skill and seemingly superterrestrial 



