233 



The young stalks entered and tunneled lengthwise, distorting and 

 stunting them (Fig. 72), the old stalks bored by caterpillars (Fig. 71) 



which pass the winter in the tap-root. .\ southern species 



The I^arger Corn Stalk-l)orer, p. 91 



Insects Injuring the Corn Plant obscurely, without \'isiblk 



Destruction of any Part of it. True Bugs (Hemiptera, 



including Plant-lice), which Suck the Sap 



through a Jointed Beak; also Thrips 



AND Ants. 



Minute slender insects not over a sixteenth of an inch long, yellowish to black 

 whigless or with delicate feathery wings (Fig. 120). Found under leaf- 

 sheaths, especially at the base of the tassel joint. On a corn leaf they 



cause whitish streaks The Thrips family, p. 135 



Corn leaves pale above, or with paler patches, and often shrunken or curved; 

 surface seemingly dirty and very finely webbed beneath. Minute rounded 



mites, visible with a glass, on under surface (Fig. 236) 



The Red Spiders {Tetranychus), p. 223 



Insects with a jointed beak at the front end of the head (Fig. 106); more or less 

 leathery wings closely applied together, nearly or quite flat on the back 

 and separated at the base by a triangular or hemispherical piece; tips of 

 wings distinctly membranous, and overlapping when folded. 2 



P'ront of head prominent, usually extending forward in a more or less con- 

 spicuous point, a jointed l)eak directed backwards from the lower hind 

 angle of the head (Fig. 110, h; 209), the wings often meeting roof-shaped, 

 not overlapping at the tip. Visible injury in the form of whitish dots on the leaf. 4 

 Minute, oval, soft-bodied, sluggish insects, clustered in colonies of old and 

 young together on leaf or stalk, usually attended by ants. Individ- 

 uals wingless or with delicate membranous wings. Growth of heavily infested 



leaves often stunted, belated, and discolored 



Plant-lice (Aphididce), pp. 123, 134, 206 



2. A small black bug less than an eightli of an inch long, the hind part of 



Ijody covered by a single large plate grooved at the edges to receive 

 the wings (Fig. 100). The Little Negro-bug (Conwe/tena puHcaria), p. 11.5 



Large broad-backed ill-smelling bugs, about half an inch long and a 

 fourth of an inch wide, with large central triangular shield on back. 



The Western Green Stink-bug (Fig. 101), p. 116 



Thycmta perditor (Fig. 102), p. 1 17 



Other Stink-bugs (Pentatomidce , Fig. 195-197), p. 194 



Large elongate bugs with leaf-like expansions on the hind legs (Fig. 

 198, etc.) Leaf-footed Plant-bugs, p 197 



Small plant-l>ugs, about a quarter of an inch long or less. 3 



3. Plants infested by small red or dusky bugs or somewhat larger black- 



ish ones with irregular white blotch on the back. These insects 

 cluster behind the leaf-sheaths of the corn on the outer surface of 

 the stalk or on the surface of the leaves, the plants wilted or other- 

 wise unhealthy, lower leaves yellow or brown (PI. I.) 



The Chinch-bug, p. 57 



Insects similar to the foregoing but grav rather than black, the wing- 

 less ones streaked witli gray (Fig. 103, 10-1) . . The False Chinch-bug, p. 117 



Plant-bugs without whitish wing-covers, foimd on corn but rarely causing 



visible injury Ligyrocoris sylvestris, p. 198 



Sphragisticus nebulosus (Fig. 200), p. 198 



Microtoma atrnta, p. 198 



The Tarnished Plant-bug (Lygiis pratevsis, Fig. 105-108), p. 118 



The Du.sky Leaf-bug (Calocnris rapidus, Fig. 201, 202), p. 199 



....The Four-lined Leaf-bug {ParAlocapsus lincatus , Fig. 203-206), p. 200 



Plngiognafhus ohscuriis (Fig. 207), p. 201 



An undetermined Leaf-bug, p. 202 



The Common Flower-ljug {Triphleps insidiosus, Fig. 208), p. 202 



4. Large wedge-shaped green or brownish species about three eighths of an 



inch long (Fig. 209, 210) The Flatas, p. 202 



Elongate, and usuallv small, leaping species (Fig. 109-114 and 212-215.) 

 ' The Leaf-hoppers, pp. 120, 121 , 204 



