48 
able to discover it. Repeated and thorough search made in “Novem- 
ber, in corn fields previously infested by both the root and aérial 
forms, as well as in fields of sorghum and broom corn, yielded not 
a single specimen. A few winged root-lice were obtained on the 7th 
of June upon the roots of corn, and, again, upon the 29th of July; 
but none others were seen during the season. 
I have not seen the corn-louse upon the foliage until after the mid- 
dle of July, but it may be found then and thereafter either upon sorghum, 
broom corn or maize, until October, infesting at first the upper 
leaves of these plants, afterwards collected upon the tassels of the 
corn, and later gathering in the silk and beneath the husks at the 
tips ‘of the ears. During all these months, wingless and winged 
females and pupse may be found together; but I am not yet able 
clearly to differentiate the successive cenerations. 
The appended table will serve to summarize the data given. 
CALENDAR OF CORN APHIS. 
| 
= gs Root Form. Aerial Form. | 
= : fy ds: hae | 
: : = 4 = = = Remarks. 
' 5 5 = is} H 8 
& Ce ell aS Shy aliamertos 
3 a 2 | au 
= na 3 na : ! : 
| 
Maiy- =... 22)\Corninnsee- 
June 1 SR Peet: 
ee 6 SEE) Sut ae 
se TAWA Seo eee Corn...- 
: Te Micra aactaans 
SRT DO! Oaeae neve 
ee xt ee 30 ayn ieee 
divitb yet aee. Silene ates | 
eee 25S or eh |seeees acre Sorghum. ....|/Sorghum..|/Sorghum../On upper leaves. 
pie) dapat x 27 Corn ees 
i aeaeee PAU is Hint ee Cornss=: 
A 31/Sorghum .|........-. Corn, broom 
corn and 
| sorghum ...|Sorghum..;Sorghum.. 
PN Te ESA GNSS ed Fe Bt | Ee pe ne Sorghum. .... ws a 
ea Prepe| ra \agetateaastonis sal eee Corny etree re: Oonnyenes: Commer | 
2S ieee ee EOS ye Re Bee Panicum...... Panicum..|Panicum..|Reared in labor tory 
Sept...-. B\COrnee eae 
os 2 All ete LR ee Nt ae pe See Sorghum and 
COrENERaeeeee | Soe ae Sorghum../Tops of sorghum 
and beneath husks 
rat | of corn. 
Corn husks... : 
Octo Les Sorzhumy 222s Sorg humm. 225 sess Tops of sorg'um and 
> bases of leaves. 
Wherever the species occurs either in the root or aerial form, 
great numbers of the common yellow ant, Lasius flavus, may like- 
wise be seen in close attendance upon it. Karly in spring this 
ant sinks its burrows beside the hills of corn, and when disturbed 
may often be seen to grasp the root-lice in its mandibles and hurry 
them away to a place of safety. Later, it attends in a similar 
manner the aérial lice upon the leaves, sharing their care in this 
stage with another species. 
It remains faithful throughout the summer, to such root-lice as. 
still occur in the ground; and it is a very unusual occurrence to find. 
