PLANT LICE. 205 
Fic. 164—Phorodon humuli Schrank.—Male, enlarged. After Insect Life, Div. of 
Entomology, Dep. of Agriculture. 
165 Phorodon humuli Schrank.—Eggs and shriveled skin of female which 
laid them, enlarged. After Insect Life, Div. of Entomology, Dep. of Agri- 
culture. 
Nothing is better than kerosene emulsion, which, when di- 
luted about ten times with water, kills all the young lice and the 
adults of the common species, providing, however, that the in- 
sects are reached with the spray, which is sometimes difficult if 
they are hidden in curled and twisted leaves. The black and 
brown species are much more difficult to kill, and we have to 
use one part of the emulsion with six or eight parts of water. 
Fish-oil soap is also a good remedy, and is effective at the 
rate of one pound in six gallons of water against the more tender 
species, and one pound in four gallons against the tougher, dark 
kinds. In every case a thorough application is essential, and if 
there is any doubt the spraying should be repeated. 
