286 



FOREST ENTOMOLOGY. 



Let us try and follow the life-history of this species Avith its some- 

 what complicated life cycle. ^ 



Generation I. The Foundress. — The first appearance of the gall 

 may be looked for, according to season, about the middle of April. 

 This is recognised by a small white speck at the tip of the shoot 

 (fig. 270), in which the mother Chermes may be found depositing her 

 eggs. This mother Chermes was hatched from a fertilised egg in 

 autumn, and spent the winter months in the larval stage. In the 

 spring the awakened larva began to feed, and after three moults she 

 became the adult foundress. In about a month's time, after the. first 



Fig. 269.— GnH o/Cliermes viridis 

 Oft spruce. 



Fig. 270. — Earlii stage of gall of 

 Chermes viridis on sirruce. 



appearance of the small white speck, the mother Chermes may be 

 found surrounded with eggs. It will be found that the cottony down 

 has increased in quantity, the young shoots developed from 1| to 2| 

 inches in length, and the pseudo-cone or gall itself from f to |^ inch 

 in length, whence arise deformed leaflets abovit \ inch in length. 



The young larvae are hatched outside the pseudo-gall, which begins 

 to enlarge before the larvae are hatched out, and it is not quite clear 

 how the vegetable structure reacts against the insect ; but the gall 

 slightly opens at the slits, and the young larvae creep in. Afterwards 



1 Having regard to the fact that this Tribe of insects has not yet received, in 

 this country, the special attention required, the brief notice here given is merely 

 an introduction to a very compHcated subject. 



