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IOWA ACADEMY OP SCIENCES. 
groups, three or four at base, followed by a group of nine, and this by two 
more widely separated, placed at distal end; radial spines, 13; anal spines,. 
5; longitudinal vein of posterior wing distinct. 
General color fuscous; third and fourth joints of antennae entirely and 
sometimes base of fifth, legs, except more or less of dorsal surface, yellow- 
ish; thorax, especially the sutures, tinged with yellow-ferruginous; abdomen 
varying from fuscous to yellowish or pale fuscous; apex always dark; dorsal 
aspect of femora generally concolorous with head; anterior wings sub- 
fuliginous with a broad, indistinctly defined, pale sub-basal band; posterior 
wings subhyaline. 
Described from eleven specimens taken at Ames, Iowa, on Cjperus, corn 
and in sweeping grass in August and November. 
GENUS CHIROTHRIPS, HAL. 
This genus is represented by a single species, Chirothrips 
antennata, Osb., which is of a brownish-black color with third 
joint of antennaB paler; second joint is quite characteristic,, 
being trapezoidal with acute angle outward. 
Ghirotlirijjs antennata, Osb. 
Can. Ent. VoL, XV, p. 154. [1883.] 
GENUS THRIPS. 
A. Head of medium size; eyes moderately prominent; antennal joints 3-5 
elongate _1 
AA. Head small; eyes very prominent; antennal joints 3-5 not elongate 
- 8 
1. Antennae eight- jointed ___2 
Antennae seven-jointed 7 
2. Sixth joint of antennae annulated 3 
Sixth joint of antennae not annulated 6 
3. Ocelli widely separated; long bristles at all angles of pro- 
thora'x; spines present at apex of ail tibiae, numerous and 
heavy on wings, on radial vein 12-14 4 
Ocelli subapproximate; single bristle of medium length at 
each posterior angle of prothorax, none at anterior angles; 
spines present at apex of posterior tibiae only, on radial vein 2 
5 
4. Size medium; head, from dorsal view, rectangulari antennae 
approximate - - [Euthrips) tritici Pitch. 
Size large; head from above pentagonal; antennae subapprox- 
imate. __ {Euthrips) maidis n. sp. 
5. Wings more or less distinctly clouded; brown markings on 
thorax and band at base of abdominal segments 2-7 distinct 
variabilis, n. sp^ 
Wings nearly uniformly fuliginous; brown markings distinct 
on thorax; abdomen immaculate var a. 
Wings and body, pale; markings, obsolete var. b. 
Wings distinctly trifasciate; broad brown band on head 
