ts ee eee ENO ee 
Sa te) a Wes cx = ; i 
On the 26th of May the winged pup found in an oat field pre- 
ponderated greatly over all the other forms and stages; a fact possibly 
to be accounted for by the relatively scanty food supply in that situa- 
tion, and the consequent necessity for migration elsewhere. June 10, on 
the other hand, in a corn field where winged specimens were present in 
large numbers, the great majority of those observed were wingless fe- 
males in various stages. 
The closely related Schizoneura corni lives from September until 
June on the dogwood (Cornus), and from June until September on the 
‘roots of certain grasses. Our collections contain species of S. corn from 
the dogwood, but the most careful investigation of our large collection 
of root lice fails to reveal any evidence of its ever having been taken 
here on the roots of corn. 
RELATIONS TO ANTS. 
The accompanying table shows that our first and last collections for 
the year were not from the roots of plants, but from the winter nests 
of ants; and here the grass louse evidently hibernates. When these nests 
are broken up, the ants evince no choice between the root lice and their 
own young in their eager and heroie efforts to carry them to places of 
safety. 
In the spring the ants dig new burrows around the roots of certain 
plants, and convey their charges to these new habitations; and during 
the summer they change them from one food plant to another, as the 
varying condition of the plants and the requirements of the root lice 
may demand. In return for these favors, this Schizoneura permits the 
ants to feed not only upon the “honey-dew” coming from the cornicles, 
but also on a waxy substance excreted from pores in the sides of the 
abdomen. We have several times seen the ants gathered about a de- 
tached mass of this wax, and apparently eating it. 
The ants collected in attendance on this root louse all belonged to 
the following forms: Jormica schaufusst, Mayr (Plate XI1., Fig. 2), 
once in attendance; L. interjectus, Mayr; L. niger, Linn., and its variety 
alienus, Forst; and L. flavus, De Geer. The ant last mentioned is per- 
haps most commonly found in charge of it, the other species of Lasius 
mentioned differing but little with respect to the frequency of their 
occurrence in this relation. 
So far as now known, this insect is little likely to eall for remedial 
measures, as corn is liable to injury by it only after grass, and the 
damage is, at most, slight and evanescent. 
DESCRIPTION.* 
Wingless Viviparous Female (Plate IX., Fig. 1).—Body ovate, 
more or less elongate, dirty white with a yellowish tinge, with a variably 
developed pattern of yellowish fuscous markings in the adult, dotted 
with white at the origin of the minute hairs which are scattered over the 
smooth surface of the body. 
Head rather small, but longer than the succeeding segments, uni- 
formly yellowish dusky, with a darker spot each side of the median line, 
a little in advance of the eye. Antenne attaining middle of side of 
_metathorax, not very thick, somewhat hairy, especially on outer joints, 
* By Mra CoAY Hart: 
