THE 
JOURNAL OF SCIENCE. 
APRIL, 1880. 
I. OUR FRIENDS AND HOW WE TREAT 
THEM. 
t NE of the most unpleasant phenomena characteristic 
of the present age is the variety and number of 
minute but formidable enemies which assail us, either 
diredtly through our persons or indirectly through our means 
of support. InseCts and Fungi seem to rival each other in 
the amount of depredation they can cause. We have, for 
instance, the Oidmm , the Phylloxera , and the Phona uvicola , 
successively ravaging the vineyards of France, and bringing 
in their train distress and destitution. We have the re- 
doubted Colorado beetle ( Doryphora ) taking a heavy per- 
centage of the potato-crops of Canada and the United 
States, and the locust of the Rocky Mountains ( Caloptenus 
spretus) widely destroying the harvests. We see the coffee- 
shrub withering away under the inroads of Hemileia vastatrix. 
Even useful inseCts, such as the silkworm and the honey- 
bee, succumb to parasitic diseases. Lastly, to complete this 
very brief sketch of minute plagues, we have flies which 
transfer from victim to victim the poison of disease, and 
make themselves the bearers certainly of carbuncle and of 
ophthalmia, and too probably of fever, cholera, and small- 
pox. There exist, we know, a certain class of writers who 
from time to time labour to prove, with an amount of sophistry 
which the most unscrupulous criminal advocate might envy, 
that all these scourges are blessings somewhat thickly dis- 
guised. Leaving these champions of nuisances to be dealt 
with by the broad common-sense of mankind, we may ask 
VOL. 11. (third series.) R 
