September, 1941 
scarcely exposed. Hemelytra pale, trans- 
lucent; clavus with a dusky cloud in middle, 
divided by pale claval vein; apex of corium 
with two small, fuscous patches; cuneus 
pale, extreme tip fuscous; membrane clear, 
veins pale. Legs pale yellowish; femora 
with a wide, fuscous band in middle on ven- 
tral side, also with two annuli near each 
apex; tibiae with a spot on knee and a ring 
just below, fuscous; spines very dark brown. 
Venter yellowish green; genital claspers dis- 
tinctive, fig. 161. 
Foop PLants.—This species is an im- 
portant pest on beans and altalfa in Idaho, 
Utah and Arizona and perhaps other west- 
ern states. Shull (1933) has discussed the 
biological and economic status of this spe- 
cies and has given it the common name “pale 
legume bug.” 
KNowNn DIstrIBUTION.—This is a west- 
tern species which migrated eastward dur- 
ing the drought years of 1930 to 1936. It is 
now known from Illinois, Iowa, Minnesota 
and all the states westward. 
Illinois Record.—I Liinois: 19. 
Lygus plagiatus Uhler 
Lygus plagiatus Uhler (1895, p. 35). 
Mave.—Length 5.30, width 2.80. More 
robust than oblineatus (Say). General color 
black with greenish yellow mottling; head 
and anterior part of pronotum yellowish or 
olive green, hemelytra irregularly mottled 
with black and less dark spots. Right 
genital clasper distinctive, fig. 161. 
FEMALE.—Slightly more robust than male 
and usually not so dark in color; second 
antennal segment shorter; pronotum jyel- 
lowish, black rays behind calli frequently not 
reaching black basal margin; venter green- 
ish yellow, blackish on the vagina exterior, 
dark specimens with black more extended. 
Foop PLants.—Giant ragweed (4 mbro- 
Sia trifida); a few Illinois specimens were 
collected on fleabane (Erigeron sp.), smart- 
weed (Polygonum sp.), willow (Salix 
sp.) and hickory (Carya glabra). The last is 
undoubtedly a “sitting” record. 
Illinois Records.—One hundred thirty- 
one males and 107 females, taken Feb. 12 
to Dec. 1, are from Algonquin, Allerton, 
Alton, Anna, Antioch, Apple River Canyon 
State Park, Ashley, Beardstown, Bloom- 
ington, Borton, Browns, Calvin, Carbon- 
dale, Champaign, Charleston, Danville, 
_ Darwin, Decatur, De Soto, Dubois, East 
KNIGHT: PLANT Buss, or MirIDAE, OF ILLINOIS 
153 
Dubuque, East St. Louis, Elizabeth, Eliza- 
bethtown, Forest City, Fountain Bluff, 
Freeport, Galena, Galesburg, Grand 
Tower, Harvard, Havana, Hillsboro, Hills- 
dale, Homer Park, Kansas, Kappa, Keiths- 
burg, Lawrenceville, Mahomet, Monticello, 
Mounds, Muncie, Murphysboro, Niota, 
Oakwood, Oquawka, Oregon, Palos Park, 
Parker, Pekin, Philadelphia, Prophetstown, 
Quincy, Rock Island, Rockford, Rockton, St. 
Francisville, St. Joseph, Sherman, Starved 
Rock State Park, Springfield, Urbana, War- 
saw, Waukegan, West Pullman, White 
Heath, White Pines Forest State Park, 
Willow Springs, York. 
Lygus rubicundus (Fallen) 
Phytocoris rubicundus Fallen (1829, p. 92). 
Matce.—Length 4.50, width 2.14. Ovate, 
robust. General color dark reddish brown 
to fuscous; second antennal segment shorter 
than width of head; genital claspers dis- 
tinctive for species, fig. 161. 
FEMALE.—Very similar to male in struc- 
ture, but usually not so darkly colored. 
Host Piants.—Peach-leaved willow 
(Salix amygdaloides) ; occurs also to some 
extent on other willows. 
Known DistripnuTION.—A common, 
Holarctic species. 
Illinois Records.—Seventy-four males 
and 70 females, taken April 15 to Nov. 15, 
are from Alton, Antioch, Beardstown, 
Bloomington, Browns, Cairo, Carbondale, 
Chicago, Dongola, Elizabeth, Elizabeth- 
town, Freeport, Galena, Galesburg, Geff, 
Golconda, Grafton, Grand Detour, Grand 
Tower, Harrisburg, Hatton, Havana, Her- 
od, Hopedale, Kankakee, Lilly, Marshall, 
Meredosia, Monticello, Mount Carmel, 
Oquawka, Oregon, Putnam, Quincy, Rock- 
ford, Savanna, Springfield, Starved Rock 
State Park, Thebes, Urbana, Volo, West 
Union, White Pines Forest State Park, 
York 
Lygus pabulinus (Linnaeus) 
Cimex pabulinus Linnaeus (1761, p. 253). 
Matre.—Length 5.50, width 2.00; body 
elongate. General color pale green or 
greenish yellow, frequently fading to dull 
yellowish; carina of vertex indistinct in 
middle; a fuscous Y-shaped mark formed 
at extreme anal area of membrane; usually 
a spot present within apices of areoles, and 
