80 
colored like the head; apical joints dark brownish, spur nearly black, 
third joint pale except near apex; six-jointed, IV and V nearly equal, 
Vea little the longer; IV’ about twice as long as thick; LI nearly or 
quite as long as LV and V combined, and equally thick; Ll about three 
fourths as thick as 1, and IIT half as thick as 1; 1 and [1 together two 
thirds the length of Ill alone; and VI half longer than V, the spur 
constituting one fourth of its length. V bears the usual round senso- 
rium, placed upon a slight prolongation of the apex beneath, On VI, at 
the base of the spur, is a round sensorium, posterior to which are three 
or more smaller sensoria, ‘The eyes are quite variable in the extent of 
the black pigment, but usually of good size. The posterior tuberele is 
distinet, and bears three equidistant oval lenses radiating from the apex 
of the tubercle. Rudimentary ocelli sometimes visible. 
The prothorax bears above an irregular oblique spot, with dark 
outline, on each side of the disk. Dark lines, in line with these spots, 
hie on each side m the transverse thoracic sutures, ‘becoming double 
posteriorly, and from these a double row of small spots continues to the 
tip of the abdomen, sometimes obscured by the discal markings of the 
segments. ‘The four segments behind the head are almost entirely fus- 
cous, except on the suture and at the sides of the first abdominal seg- 
ment. ‘The three or four segments preceding the cauda are yellowish 
fuscous except near the lateral margin. The other abdominal segments 
show faint mottled tuscous bands. ‘The cornicles are very distinetly 
indicated by fine dark rings nearly level with the surface, surrounded 
by a dark bloteh. Cauda very short, subtriangular, not projecting, it and 
the anal plate yellowish fuscous, hairy. 
Beneath slightly paler than above, with markings of similar color; 
legs and beak brownish yellow. ‘The beak attains the base of the abdo- 
men, last two joints dark brownish yellow, tip black. The basal two 
joints are together about twice as long as the third and fourth com- 
bined. The third joint is slightly broader than the others, about as 
long as broad; the fourth joint is half longer, pale-ringed just before 
the tip. Legs nearly smooth, femora darker apically, tibie paler ex- 
cept at base and apex, claws dark, large. ‘Che abdomen has a marginal 
row of dark blotches, in which are situated the spiracles, and above 
these, a large subcireular excretory pore on segments 1-4 and 7. A 
similar large oval pore lies just below the lateral margin of the pro- 
thorax. These are homologous with the tubercles of the corn root louse, 
and perhaps with the cornicles also. Below the spiracles is a row of dark 
spots in the sutures. The seventh segment bears the usual transverse 
oblong brownish yellow plate. 
Length 1.5 mm., breadth .9 mm., antenna .5 mm, 
Described from numerous specimens from roots of grass and corn, 
''The young show the usual differences of size and color, and pro- 
portionate greater length of appendages. The antennw have but five 
joints, the third proportionally shorter. 
Pupa.—Oval, more clongate, yellowish white, head and thorax 
dusky, no distinct markings except the double row of spots. Antenne 
about attaining base of posterior wing-pads, with suture between IT] 
and TV imperfect. Wing-pads attaining middle of second segment be- 
