446 MODERN CLASSIFICATION OF INSECTS. 
nate them. Some of the species infest the vine, pine-apple*, and orange 
trees in hot-houses, where they do great damage ; the continued heat 
and, as Mr. Curtis well suggests, the absence of those parasites which, 
in the native countries of those plants, keep them in check, rendering 
their propagation continuous, and not annual, as in the out-of-door 
species. Sometimes they are so numerous, that I have seen instances 
in which the entire surface of a branch of an apple tree has been com- 
pletely covered with them. ‘They are well known to gardeners and 
others under the name of scale insects and mealy bugs; the former, 
especially, affixing themselves to the twigs; and the females, by de- 
grees, assuming the appearance of galls, whence they are termed 
by the French gall insects. The males, in their earliest states, re- 
semble the females; but a period arrives when the individuals of 
this sex undergo a singular change. At this time, they affix them- 
selves to the plant for a certain period, sufficient to allow them to 
undergo their transformations ; the pupa being inactive, and covered 
by the skin of the larva, or by an additional pellicle (fig. 118. 21. 
cocoon of C. cryptogamus Dalm. 3 ). 
The following account of the habits of Coccus aceris, communicated 
by me to Mr. Curtis, from my observations continued through severa 
years, will sufficiently show the habits of the family : — 
The males make their appearance in the winged state in May, when 
the impregnation of the female takes place, in the singular manner de- 
scribed by Réaumur (Mém. tom.iv.). The males, on escaping from their 
singular cocoons, escape backwards, the wings being extended flatly 
over the head. By the end of June the females have attained their 
full gravid size ; and, on lifting up their bodies, their whole interior, 
or the entire space between the under surface of the body and the 
bark of the tree, is occupied by white flowery-like matter, in which 
the minute young are to be observed, of the size of the smallest dot ; 
the dead body of the parent forming a covering to the young. In this 
state they are hexapod, antenniferous, active, and furnished with two 
long anal sete. By the end of July the young quit the body of their 
parent, and ascend to the extremity of the young branches; there 
they affix themselves by their rostrum, gradually increase in size, and 
lose their anal sete, as well as their former activity. In this state 
they remain through the winter, without any diversity of appearance 
* See my Observations on two species which infest pine-apples, in Trans, Ent. 
Soe. vol. i. p. 206. 
