168 HALF HOUES WITH INSECTS. [Packakd. 



one female, and the former appear to perform the chief part 

 of the labor in the excavation of their galleries. With the 

 timber beetles, on the other hand, the females are much the 

 more numerous, and probably mine their galleries without 

 any assistance from the other sex. M. Ferris states of one 

 of the species, that upwards of fifty females were met with 

 in the burrows they had excavated, without a single male 

 being found there." 



As the young hatch out they run galleries either at right 

 angles to the original one, or branching out in every direc- 

 tion, though never intercrossing. In this way those that 

 confine themselves entirely to the sap wood and inner bark 

 loosen it, interrupt the circulation of sap and kill the branch 

 affected. 



The Apple Tivig Borer or AmpMcerus bicaudatus (Fig. 

 133) is an exceedingly annoying beetle in the middle and 

 Fig. in.3. western states. It somewhat resembles the bark 

 boring beetles, but belongs to a different family. 

 The grub is not known with certainty to burrow 

 in the apple, but the beetles late in the summer 

 bore into the twigs of the apple, beginning, ac- 

 Amphiceius. cording to Rile}', just above a bud or fork, whence 

 it bores downwards an inch and a half into the twig, usually 

 in wood of the previous j-ear's growth. "Both the male and 

 female beetles bore these holes, and may always be found in 

 them head downwards during the winter and spring months. 

 The holes are made for food and protection, and not for 

 breeding purposes." As a preventive measure the infested 

 twigs should be cut off and burned, the trees being looked 

 over in the autumn. 



The PricMy Leptostylus is the last borer which we have on 

 our list of boring beetles. Dr. Fitch says that the grubs 

 are like the young of the apple tree borer, and sometimes 

 "occur in multitudes under tlie bark, forming long, narrow, 

 winding tracks upon the outer surface of the wood, these 



