484 PROCEEDINGS: BOSTON SOCIETY NATURAL HISTORY. 
Key to Species of Melanoplus, 
Males. 
a. Tegmina no longer, or but little longer, than the pronotum. 
b. Furcula large, nearly twice as long as last dorsal segment, its fingers 
broad, flat, tapering. Cerci short, flat, scarcely twice as long as their 
basal width, rapidly narrowed dorsally on basal half to one-half or 
one-third their basal width, thence equal, curved upward, with blunt, 
almost truncate apex. 
Dawson's Locust, M. dawsoni, p. 516. 
bb. Furcula very short, often scarcely noticeable. 
c. Cerci relatively broad throughout, usually somewhat triangular. 
d. Hind tibiae greenish. Subgenital plate very short (its ventral 
margin less than its depth), ending in a very acute, upturned 
tubercle. Cerci very nearly symmetrical. Color black or greenish 
gray, lateral stripe of pronotum broad, percurrent; hind femora 
fasciate Green-legged Locust, M. viridipes, p. 522. 
dd. Hind tibiae red. Subgenital plate conical, bluntly pointed, little 
upturned. Cerci with ventral margin strongly convex, dorsal 
margin concave, a little twisted near apex, which is shallowly 
sulcate externally Scudder's Locust, M. scudderi, p. 520. 
cc. Distal half of cerci narrow, less than half as wide as base. 
e. Hind tibiae red. Tegmina shorter than pronotum. Cerci nar- 
rowed rapidly on dorsal side of basal half to one-third or one- 
fourth their basal width, the distal half of nearly equal width 
throughout, curving slightly upward and inward, flattened exter- 
nally, apex bluntly rounded.. . .Smith's Locust, M. manciis, p. 518. 
ce. Hind tibiae greenish blue. Tegmina longer than pronotum, lan- 
ceolate, acutely taper-pointed or acuminate. Cerci straight, erect, 
tapering equally on basal half or two-thirds, the tip very nar- 
row, pointed. Head exceptionally large. Probably adventive. 
Large-headed Locust, Phoetaliotes nebrascensis, p. 524. 
aa. Tegmina much longer than pronotum. 
/. Subgenital plate distinctly notched apically. Tegmina reaching or 
passing hind knees. Cerci short, scarcely twice as long as wide; and 
subtrapezoidal, the distal margin oblique, the apex dorsal and broadly 
rounded Lesser Migratory Locust, M. mexicanus atlanis, p. 499. 
ff. Subgenital plate not notched at apex. 
g. Cerci simple in outline, nearly straight. 
h. Furcula very short. Cerci long, three to four times as long as wide 
and subequal in width throughout; apex rounded, a little ventral. 
Huckleberry Locust, M. fasciatus, p. 50L 
hh. Furcula long, much longer than last dorsal segment. 
i. Cerci tapering, the distal half less than half as wide as extreme 
base Red-legged Locust, M. femur-rubrum, p. 503. 
