28 



On reaching full growth, early in the summer, the female insect 

 deposits her eggs beneath her already much-hardened parchment-like 



skin, the lower surface of 

 the body gradually contract- 

 ing until there is nothing left 

 but the shell, covering a mass 

 of hundreds of eggs. The 

 eggs will hatch in a compar- 

 atively short time, but, as the 

 females come to maturity at 

 different dates, the young 

 from this species are con- 

 stantly appearing and spread- 

 ing over the infested plants 

 between June and the end of 

 October. The growth, how- 

 ever, is very slow, and even 

 those earliest hatched do not 

 reach maturity until late in 

 autumn, the latest maturing 

 in June and July of the fol- 

 lowing year. 



While retaining the power 

 of movement practically 

 throughout its development, 

 this scale insect is very little 

 apt to change its position 

 after it is once settled, or, at least, after it is half grown. There 

 is a general migration from leaf to twig, but the scale often develops 



Fig. 19. — Black scale (Lecanium olex): a, greatly en- 

 larged drawing of newly hatched larva, viewed from 

 beneath, with enlargements of anal extremity viewed 

 from above — 6, showing anal segment extruded, and 

 r, .'iame retracted (original). 



F^G. 20. — Black scale {Lecanium. olex), male series: a, fully developed male scale; 6, pupa; c, winged 

 adult— natural size indicated by hair lines (original). 



on the leaf if the latter remains vigorous and supplies it sufficient 

 nourishment. 



