196 



ENTOMOLOGY. 



Remedies. — Burn the stubble, old straw, and corn-stalks among 

 weeds in fence-corners in the early spring. Sow small grain early 

 in the spring; fall ploughing and the use of the 

 roller upon land that is loose and friable are 

 recommended. Where irrigation is practised, 

 fields may be flooded for several days in suc- 

 cession, and thus the insects driven off or 

 drowned. A kerosene emulsion, sprayed with 

 the force-pump and cyclone nozzle, will de- 

 stroy immense numbers; and deep furrows, 

 with a log drawn through them to grind the 

 soil into dust, will also prove useful in arrest- 

 ing their progress. 



Fig. 239.— Chinch-bug. 



Grain Aphis {Aphis avence Fabr.). — 

 Multitudes of dark plant-lice, clustering 

 on the heads of wheat in August; in 

 certain years blacken the fields of grain, and by sucking 

 the kernels cause them to shrink in size and to diminish in 

 weight. 



The Northern Army-worm (Leucania unipuncta Ha- 



worth). — This caterpillar periodically ravages wheat and 

 other grain fields in the Middle and Northern States, march- 

 ing through them in great armies. The 

 moth appears late in the summer or 

 early in autumn, when it hibernates, 

 after laying its eggs near the roots of 

 perennial grasses; or farther south it 



Fig. 240.— Northern army-worm, a, moth, with details.— After Riley. 



hibernates in the chrysalis state, laving its eggs in April 

 and May, but later northward. The eggs hatch, the young 

 appearing eight or ten days after, and the worms are most 



