172 
THE STUDY OF INSECTS. 
Scale, and of many other forms, the scale-like object com¬ 
monly seen is not the insect, but an armor beneath which it 
lives. 
The young insects of this sub-family resemble in general 
appearance those of other scale insects. Their active stage, 
however, is much shorter. After crawling about over the 
i lG * 2I2 «—Chionaspis pinifolite; 2, scales on Pinus strobus, natural size, leaves stunted; 
2<z, leaves of P. strobus not stunted by scale insects; 2 /5, scale of female, usual 
form, enlarged; 2 c, scale of female, wide f jrrn, ; si, scale of male en¬ 
larged. 
twigs of a tree for a few days, the young scale insect settles 
upon a suitable place and immediately begins to excrete 
a cottony substance which soon becomes compacted into a 
thin pellicle covering the body. As the insect grows and 
needs to shed its skin, this cast skin is joined to the excretion 
and forms a part of the scale. This is the bright-colored, 
nipple-like prominence, seen in the centre of the Pernicious 
