﻿48 



EIGHTH ANNUAL RERORT 



THE FALL ARMY WORM. 



This worm not only acts at times like the Army Worm proper, 

 but bears a very close general resemblance to it, so that it is not sur- 

 prising that the two insects should have been so often confounded. 

 Keports of the appearance of the Army Worm in the Fall, such as that 

 recorded by Prof. Thomas, and which greatly influenced him in his 

 belief that our Leucania was double-brooded,* are easily explained 

 by what we now know of this Fall species. Having already given an 

 extended account of this last in my 3rd Keport,f it will suffice in this 

 connection to repeat the leading facts in its history, so as to show 

 how it may be distinguished from the Leucania. 



The Fall Army Worm — unlike the Leucania, which confines itself 

 for the most part to grasses and cereals — is a very general feeder, de- 

 vouring with equal relish most succulent plants, such as wheat, oats, 

 corn, barley, grasses, purslane, turnips, most garden vegetables, and 

 even spruces. Though variable in color, when carefully examined it will 

 be found to invariably differ from the Army Worm in the following 

 more noticeable points : 1. It never becomes quite so large ; 2, the 

 head is smaller, darker, with a conspicuous white, V-mark, not pos- 

 sessed by Leucania; 3, the lateral dark and pale lines are broader 

 and the former bordered above by a much more distinct white or yel- 

 lowish, narrow line; 4, the piliferous spots and hairs, which in Leu- 

 cania are so obsolete that the worm appears perfectly smooth, form 

 conspicuous polished black tubercles that give rise to short, stiff, 



black hairs. Compare 



figs. 20 and 26, a. Thus, 



whenever worms are 



found mowing down 



grain in the Fall of the 



year, the presence of 



these easily observed 



black tubercles will al 



once show that they 



are not the genuine 



Army Worm. The 



Fall Akmy Worm -.—a, full 



Fall Army AVorm ]\roTii :— «. 



^•own wonii, nat. size ; li, lic;i(l, motll, WhlCh belOUgS the typiciil Ibrm ; b, c, v:iri;ition8 

 Irniii front ; r, ioint of hody, of wings, 



dorsal view ; d, do., side view- ^q GuBnce's Family 

 enlarged. 



* Prairie Farmer, Nov. 7, ISGl. 



jThis insect was there described as Prodenia autumnalis. Further investigation shows it to be the 

 "Corn-bud worm moth" of Smith & Abbott, (Ins. ot Ga., W) figured by them as PhaUcna fnigi- 

 perda, and subsequently described by Guence under the genus Laphygma, wh-ich is separated from 

 Prodenia by a few rather trilling characters. 



