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ARTICLE III.— BRIEF NOTES ON SORGHUM INSECTS. 



My last report contained a paper on such insects as infest the 

 sorghum plant as were then known to me, and to these I now add 

 a few notes on one of the species therein treated, together with a 

 description of a second species occurring upon the roots, first 

 observed this year. 



1. The Yellow Sorghum Plant Louse. 



{Chaitophorus Jiavus, Forbes.) 



Order Hemiptera.. Family Aphidid^. 



(Plate VL Figs. 1-4.) 



This species, discovered last year, was first observed July 25, and 

 the facts of its earlier life history were of course unknown, but our 

 observations of the present season carry the record a month farther 

 back. 



On the 2-th of June, in fields of sorghum at Champaign which 

 had been replanted, when the plant was only three or four inches 

 high and showed but three or four of the leaves, one of these was 

 occasionally reddened with a small cluster of the above plant lice 

 beneath it. Each of these consisted of a single full-grown female 

 (winged in all cases but one) surrounded by a group of wingless 

 young, sometimes evidently but just born. One of these winged 

 females was dead in the center of a group of still living young. 

 These fields were a.mong those worst infested by this louse last year. 



I searched carefully and extensively for root lice, but in vain. 

 Every stalk seen which showed any signs of ill condition was dug 

 up and examined, but no root lice of any sort were found. It 

 seems probable, consequently, that the Chaitophorus emerged from 

 the ground in spring, crawled up to the lower leaves of the young 

 plant, and there commenced at once to multiply ; and it seems 

 unlikely that any root form of this species will be found. This 

 year, as last, I noticed that the ants paid no attention to this plant 

 louse, although Laskis flavus and other species were not uncommon 

 in the fields at the time. 



