INSECTS INFESTING THE APPLE TREE. 



59 



May, and, so far as known at present, there is only one brood 

 in each year. Larva length, one seventieth of an inch ; color, 

 pale yellow; form, ovoid; antenna, seven jointed, two anal 

 setae. In a few days after it is hatched the larva fixes itself 

 on the wood, leaves or fruit, and perfects its change, or meta- 

 morphosis, as shown in Fig. 13. 



Fig. 13. 



Fig. 13. — Oyster Shell Bark-louse, highly magnified. /, the 

 egg — color, white or yellowish ; 2, the newly hatched larva — 

 color, yellow ; 3, the larva after becoming fixed ; 4, the scale 

 after the second plate is formed ; 7, fully formed scale, ventral 

 view ; -5, ventral view of larva ; 6, adult female — color, pale 

 yellow ; <?, antenna of the larva (2). 



The male (perfect) insect is winged, as shown in Fig. 14. 



Fig. 14. 



Fig. 14. — Oyster Shell Bark-louse (male), highly magnified; 

 a, ventral view of winged male — color, gray; /, a joint of his 



