SCALE-INSECTS, BARK-LICE, MEALY-BUGS. 241 
later the females deposit their tiny eggs, which fill all the space 
beneath the protecting scale. 
Remedies. 
A numer of remedies against scale-insects have already 
been given, and it is only necessary to make some general re- 
marks. It should be remembered that insects so well covered 
with waxy scales, cottony matter, or some powdery material, are 
not so easily reached by insecticides as the plant-lice. In many 
cases liquids will run off so quickly that they do not remain in 
contact with the scales long enough to do any effective work. 
For this reason we must apply insecticides, which remain in 
pling 
Fig. 194.—Parasite of Grain-louse. Adult Fig. 195.—Another parasite of the 
and infested louse, showing hole through Grain-louse. After Smith. 
which the parasite escaped. After 
Smith. 
actual contact for some time, and for this reason kerosene emul- 
sion and whale-oil soap are most excellent. When we have to 
deal with very smooth scales the whale- or fish-oil soap solu- 
tions are best. If possible, radical winter treatment is best. But 
there is a period in the life-history of all these scale-insects when 
the young insects are as yet not covered with a protecting sub- 
stance, but are actively running about searching for a place on 
the infested plant upon which to fasten themselves. If during 
this period we apply kerosene emulsion diluted not more than 
five times with water or soap-suds, we can kill the majority of 
these still small and weak beings. 
