( 68 ) 
Uhler’s description as follows : The black stripe on the side of the 
female pronotum is distinct and broad ; whitish spots on the meta tho- 
rax distinct in the male ; posterior femora yellow or greenish-yellow, 
with distinct oblique dark bands ; posterior tibiae pale. 
36. Pez. viola, sp. nov. 
Female. Rather large and robust, caloptenoid in appearance, and 
resembling somewhat Pez. dodgei. Vertex and frontal costa not, or 
but slightly, sulcate. Pronotum with the median carina slight; lateral 
carinae somewhat distinct ; sides flattened ; posterior margin rounded ; 
posterior lateral margins with a distinct inward curve or rounded 
notch at the humerus, the portion below the notch perpendicular. 
Elytra ovate-lanceolate, the externo-median nerve distinct, not always 
meeting at the base, but overlapping more or less toward the apex ; 
varying in length from about one-third to more than one-half that of 
the abdomen. 
Color. Varying from a dull olive-brown to ash-brown. Head and 
thorax brown ; elytra with the upper (or inner) half pale brown, lower 
(outer) half dark-brown or black, one or two dots sometimes broken off 
the black at the tip : posterior femora reddish with oblique brownish 
bands ; posterior tibiae rufous. 
Dimensions. Length 1. to 1.1 inch. 
Central and southern Illinois. 
37. Caloptenus femur-rubrum, Deg. 
Acrydium femur-rubrum, Peg. Ins., Ill, 498, PI. 2, Fig 5. 
femorale, Oliv. Encyc. Meth. Ins., VI, 228. 
G-ryllus (Locusta) erythropterus, G-mel. Linn. Syst. Nat., I, 2086. 
Caloptenus femur-rubrum, Burm. Handb. Ent., II, 638. 
Pezotettix (Melanoplus) femur-iubrum,Stal. Recens. Orthop , I, 79 
Our most common species ; found throughout the state. 
38. C. atlantis, Riley, 1st Rept., 1875. 169. 
This is but a variety of the preceding species, and appears to be an 
intermediate link betwean C. femur-rubrum and C. spretus ; but in 
some respects approaches C. occidentals. 
39 ? C. spretus, Thos. (The Rocky Mountain Locust.) 
Acridium spretum, Thos. Trans. 111. Ag. Soc., V, 450. 
Caloptenus spretus, Thos. Synop. Acrid , 164. 
A few stray specimens have perhaps been captured in Illinois, and 
hepce I include it with a mark of doubt prefixed. 
40. Acridium differentiale, Thos., Trans. 111. Ag. Soc. ; V, 450. 
. Cyrtacanthacris differentials, Walk. Cat. Bermap. Salt., J.V, 610. 
Caloptenus differentialis, Thos. Proc. Acad. Nat. Sci. Phila., 1871. 
Common throughout the state, and has occasionally been seen mi- 
grating. 
