SCALE-INSEOTS. 27 
II. Neglecting entomological distinctions, we may divide 
the Coccididee, roughly, into— 
(a.) Insects attacking deciduous plants ; 
(6.) Insects attacking evergreen plants ; 
or, again, 
(c.) Insects living usually on the bark ; 
(d.) Insects living usually on the leaves ; 
(e.) Insects living on both bark and leaves ; 
or, lastly, 
(f.) Insects covered with hard shields or “scales ;” 
(g.) Insects covered with cotton; 
(A.) Insects naked. 
It will be clear that a different method will be required for 
destroying these different classes ; but any one insect will belong 
to more than one class. Thus Mytilaspis pomorum, the apple- 
scale, belongs to (a), (c), and (f), and indeed may be placed 
also im (4), as such plants as hawthorns, which it attacks, are 
as bad as evergreens in the difficulty of reaching the insect on 
them ; or, Lecanium hesperidum is in (a), (d), and (A) ; Lecanium 
olee in (a), (0), (e), and (A). 
As far as regards the injurious species of Coccids it may 
usually be taken for granted that those infesting deciduous 
plants (class a) live chiefly on the bark (class ce), and are either 
naked (class h) or covered with a hard scale (class f). If naked 
they are chiefly Lecanium ; if covered, either Mytilaspis, Aspidio- 
tus, or Diaspis. 
Icerya is exceptional, being omnivorous, feeding equaily on 
bark or leaves, deciduous or evergreen plants ; it belongs to 
every class except (f). Every method of destruction has therefore 
to be resorted to against it. 
The treatment of a deciduous plant infested by Coccids is 
simple as to its method. For two reasons the dead winter-time 
must be chosen for it—first, because, the leaves being off, the 
whole plant can be easily got at; secondly, because the eggs of 
the insect have not yet been hatched, and the whole brood can 
be destroyed at once. ‘The first operation should be the pruning 
of the tree, so as to reduce the labour required to a minimum. 
A brushing over all the trunk and branches with a good hard 
stiff brush and one of the liquid remedies given below is then 
often successful. Brushing with a dry brush is adopted by 
some persons; but, although this doubtless clears away a good 
