THE ARMY WORM, 



{Heliophila unipuncta, Haworth.) 



By Dr. H. T. Fernald. 



The army worm is widely distributed over the United 

 States and from time to time causes considerable loss. 

 Usually it is not abundant, but after a period of a dozen 

 or more years it suddenly appears in large numbers, feeding 

 upon various plants, and marching in armies attracts much 

 attention. The present season has been one of its years of 

 unusual abundance in Massachusetts, and this has led to 

 many inquiries about the insect, its habits, methods of con- 

 trol and the chances that it may reappear another year. 

 These inquiries have led to the publication of this paper. 



History. 



Records of previous years of abundance of the army 

 worm in Massachusetts are not as complete as could be 

 desired. Nevertheless, old diaries and journals give some 

 evidence as to early periods of abundance in New England, 

 which may be of interest. Flint summarizes weather and 

 crop conditions from records from various sources. Here we 

 learn that "the next dry summer was in 1666, when most 

 of the grain was scorched up and the Indian corn eaten by 

 the worms. In 1743 there were millions of devouring worms 

 in armies, threatening to cut off every green thing. In 1770 

 'a very uncommon sort of worm called the canker worm 

 ate the corn and grass all as they went above ground which 

 cut short the crops in many places.'" As the true canker 

 worms feed on the foliage of trees, the use of this name here 

 is manifestly incorrect. This appearance of the insect is 

 also recorded by Noah Webster, and in more detail by 



