THE INJURIOUS SCALE INSECTS AND MEALY BUGS, &c. 229 
common pest on cultivated Roses, and for this reason is one of the best 
known coccids in the British Isles. 
The covering scale of the female is pure white, and comparatively 
thick, the larval moult appearing towards the margin as a yellow speck. 
The male scale is also white, occurs as freely as those of the opposite sex^ 
and resembles that shown of the next species. (Fig. 99, C.) 
The adult female is deep orange-red, and in shape remarkably 
resembles certain Trilobites of the older geological deposits, and is the 
largest of all the British Diaspina?. 
The male pupa, larva, and ova are of a similar colour to the female, 
varying only in the intensity of the orange-red or orange-crimson. 
The habit of this species is to thoroughly infest the main stems of the 
Wild Rose (briars), only ascending to the smaller branches when 
overcrowding compels them. Under glass and in warmer countries they 
will take greater strides and also infest the leaves, which not infrequently 
proves fatal to them, as when the leaves fall they are naturally cut away 
from their food supply. It is owing to the persistent habit of infesting 
briars that these insects are brought into our nurseries ; and although 
they may not at first be numerous, they will in time cover the 
" standard," much to the detriment of the plant. 
Fig. 98.— Scurfy Eose Scale 
(Diasjpis toscb) on stem of Wild Hose' (nat. size). 
