97 



borer upon the plantation of Dr. J. 1>. Wilkinson, some 40 miles south 

 of New Orleans on the Mississippi Kiver. Dr. Wilkinson informed me 

 that in 1857 they were very abundant in the Lower ^lississippi, and 

 that the crop upon one plantation was utterly destroyed, the cane 

 breaking to pieces as they attempted to cut it. A summary of the ob- 

 servations which I made at that time was publisluMl in Special lie[)ort 

 No. U of tlie Department of Agriculture, an<l .in the Annual Keport 

 for 1880, pp. 240-242. 



The life history as then ascertained is brietly as follows: In early 

 spring tlie parent moth lays her eggs upon the leaves of the young cane 

 near the axles and the young borer penetrates the stalk at or near the 

 joint and commences to tunnel, usually upwards, through the soft i)ith. 

 The larval growth is rapid and the borer is active, and frequently 

 leaves the stalk at one place and enters at another, making several 

 holes in the course of its growth. AVheu ready to transform, it bur- 

 rows to the surtace, making a hole for the exit of the future moth, and 

 transforms to the pupa state. There are several generations in the 

 course of a season and the insect hibernates in the larval state within 

 the stalks. 



It must be a number of years since what is apparently this same 

 inse(!t tlrst transferred its attentions in part from sugar-(;ane to corn, as 

 it is figured upon one of Glover's unpublished plates as " injuring 

 maize in South Carolina." In July of 1881 specimens of the insect were 

 received from Abbeville County, S. C, and were studied at tbe Divi- 

 sion of Entomology. The considerable damage which was done in that 

 locality was treated in the Annual Report of the Department of Agri- 

 culture for 1880, pp. 243-245. It was also received about the same time 

 from Lincoln County, Ga., where the damage to the corn crop was esti- 

 mated by a correspondent of the Department at from 10 to 25 per cent. 



Late in the summer of 1881 I was sent by Professor Riley on a trip 

 through South Carolina and G-eorgia, principally to study rice insects, 

 but also to give some attention to the smaller corn stalk-borer {Pem- 

 pelia ligrwseUa). I then incidentally found the work of this larger borer 

 in an extensive field near Atlanta, Ga., and very abundantly near 

 Columbia, S. C, upon the plantation of Mr. James Sims. It was there 

 the exception to find a stalk which had not one or more holes in it. The 

 work of the late broods had not apparently injured the " make " very 

 much, and frequently a stalk which had contained several larvae bore 

 its full and hard ears of corn. The early weakening of the stalk was 

 what had proved destructive. The worm seemed never to deform the 

 stalk, and the larva was almost invariably found above ground in the 

 first three sections. I found one stalk, for instance, which in these 

 three sections was riddled by no less than thirty holes and the center of 

 which was comi)letely eaten out. According to my observations in that 

 locality, the insect was confined to high ground, and no trace of it was 

 found in the cornfields along the Congaree River, where I studied 

 Bill-bug damage to the corn crop. 



