New York Agricultural Experiment Station. ^>>1 



which includes the iiight flying moths. It is also interesting to 

 note that this insect is closely related to some of our most de- 

 structive cutworms. 



8o7nc habits of the army worm, Leucania iinipuncta. — Although 

 unsuspected by most of us, the army worm is present in some of 

 our fields every year. The grass land is its natural home. The 

 caterpillars are usually found in those places where the grass 

 grows most luxuriantly. Here they may remain season after 

 season, one brood following another, feeding unnoticed almost 

 before our eyes. It is not until meteorological conditions are 

 favorable for them, however, that the abnormal increase occurs. 

 It is only at such times that the unusual habit of moving in vast 

 armies is developed. As a rule also, it is said, the caterpillars 

 are usually nearly half grown before the march in search of food 

 begins. They seem to be especially ravenous at this time and the 

 rapidity with which a field of grain may be ruined is truly sur- 

 prising. An acre or more of corn may be destroyed in a single 

 night. The caterpillars usually feed more rapidly at night than 

 during the day, although they are very active on cloudy days or 

 during the cool of a bright day. 



Life-history and descriptions. — The life-history of the army 

 worm, Leucania unipuncta, together with descriptions of the dif- 

 ferent changes which take place during the life cycle, may be 

 briefly stated as follows: The mature insects are dull brown 

 moths having a white spot in the center of each anterior wing. 

 When the wings are spread a single female moth will measure 

 over an inch and a half from tip to tip. The body is about three- 

 fourths of an inch long. 



The eggs are very small, globular in form and nearly white in 

 color. They are usually laid in the leaf sheaths of grasses and 

 grains, the terminal sheath being most frequently selected. Ac- 

 cording to Dr. Riley* the early brood of moths oviposit freely 

 *' in the cut straw of old stacks, in hay ricks and even in old fod- 

 der stocks of corn stalks." He also adds that '' old bits of corn 

 stalk upon the surface of the ground in pastures have been re- 



* U. S. l)ept. Agr. Kep. 1881-2, pp. 9001. 



