90 NORTH AMERICAN INSECTS. 
duces it so fast and so abundantly, that, were the consump- 
tion of shellac ten times greater than it is, it could readily 
be supplied. 
There are many other species of Shield-lice found in the 
old countries, which have from time immemorial furnished 
a substance used for dyeing red, and which are still used 
for that purpose. Hence their name among the Greeks 
and Romans was “ Coccus,” by the Arabs called “‘ Kermes,” 
and by the Persians “‘ Alkermes.” 
Professor Ehrenberg, of Berlin, to whom the science is 
so much indebted for his laborious microscopic investiga- 
tions of the Animalcules, found large Tamarisk-trees (Zam- 
arix mannifera, Ehrenb.) upon Mount Sinai, the young 
shoots of which were covered with a species of Shield-louse, 
which he called Coccus manniferus. 
These insects, by puncturing the branches with their pro- 
boscis, cause them to discharge a large quantity of gummy 
secretion, which very soon hardens and drops from the tree, 
when it is easily collected by the natives, who believe it to 
be the real manna of the Israelites. 
Our currant bushes, young apple, and peach trees, often 
suffer from the ravages of different species of bark-lice, and 
not unfrequently are destroyed by them. Many small birds 
feed principally on these species of Lice, but, in spite of 
this, their multiplication is often so great that we must 
rely upon other and artificial means to destroy them. 
Dr. Harris, of Cambridge, mentioning them in his “ Re- 
port on the Insects of Massachusetts Injurious to Vegeta- 
tion,” says: ‘The best application for the destruction of the 
Lice is a wash made of two parts of soft soap and eight of 
water, with which is to be mixed lime enough to bring it 
to the consistence of thick whitewash. This is to be put 
upon the trunks and limbs of the trees with a brush, and 
as high as practicable, so as to cover the whole surface, 
and fill all the cracks in the bark. The proper time for 
