A OE 
Although the species are generally credited with only one tarsal 
joint and one posterior claw, I am inclined to think that a minute first 
tarsal joint of the usual form is really present; and the claws of the 
posterior tarsus, although smaller than the others, seem to be both dis- 
tinctly present in the species here described. 
No winged forms of Rhizobius have ever been reported, yet there 
is in our collections a singular pupa, evidently of this genus but of a 
different species, having well- developed wing- pads. 
Rhizobius panici, Thos. (Lychea panici) is closely related to this 
species, but differs distinctly in the antenne and beak. Rhizobius poe, 
Thos., appears to be a Dactylopius. 
Tus SoraHum Meaty Bua. 
(Dactylopius sorghiellus, Forbes.) * 
(Plate X., Fig. 7 and 8.) 
This mealy bug is an oval, distinctly segmented, reddish or flesh- 
colored insect, cov ered with a bluish w axy bloom, and commonly bears 
a thicker mass of waxy substance imbedding the bases of a tuft of hairs 
at the tip of the abdomen. It is about .07 inch long, and about as thick 
as wide, its width between a third and a half of its length. It has a 
pair of short, eight-joimted antenne, and a black simple eye on each 
side of the head. 
It is of common occurrence on corn, generally infesting the roots, 
and usually found only where the corn has been planted on sod. It is 
doubtless normally a grass insect. It was first reported by me in 1885 
as a sorghum insect, and described under the name of Coccus sorgliellus 
in my Fourteenth Report as State Entomologist of Illinois (p. 71). It 
has since been found by us on corn (roots, “leat sheath, and leaf), on 
sorghum (August 4), and on the roots of June grass, timothy, and prob- 
ably other meadow and pasture grasses, clover, and cocklebur (Xanthiwm 
strumarium). It is commonly attended by ants, especially the pee 
most frequently acting as host to the corn root aphis, Lasius niger a 
its variety alienus. It sometimes passes the winter in their nests, ieee 
we have seen ants feeding on the waxy surface-covering of the mealy 
bugs. 
Its methods of multiplication are similar to those of the plant lee, 
viviparous females producing young in spring, and a sexual oviparous 
generation appearing in fall. We have found adults in the earth on the 
roots of grass (timothy) March 24, and have collected them from earth, 
among the roots of clover, May 14. May 15 we have taken them from 
the roots of young corn with the small brown ant Lasius niger alienus 
in attendance, and May 17 have seen adults and half-grown young to- 
gether in the same sHnetioah The young thus seem to make their “frst 
appearance for the year in the early part ‘of May. May 18 and 19 many 
specimens were obtained on corn roots at Champaign, and at Polo in 
northern Illinois, those at the former place rapidly producing young by 
viviparous generation. These were at this time scattering over the corn 
plant, and were most abundant in the youngest folded leaves. This 
* Coccus sorghiellus, Forbes, Fourteenth Rep. State Ent. Ill. p. 71. 
