362 FAMILY VI. ACRID1D.E. THE LOCUSTS. 



e. Tegmina shorter than or but slightly longer than pronotum, at 

 the most but slightly overlapping, their dorsal and median 

 areas but feebly if at all defined. 



f. Median carina of pronotum distinct only on metazona and some- 

 times the apical third of prozona; tegmina with dorsal mar- 

 gins well separated, rarely subattingent in male: prosternal 

 spine, short, conical or pyramidal; furcula as long or longer 

 than last dorsal segment. SERIES V, p. 386. 



ff. Median carina of pronotum low but distinct throughout; teg- 

 mina with dorsal margins attingent or slightly overlapping, 

 their tips subacute or obliquely rounded; prosternal spine 

 longer, subcylindrical with blunt rounded apex; furcula (ex- 

 cept in dawsoni) distinctly shorter than last dorsal segment. 



SERIES VI, p. 391. 



ee. Tegmina distinctly longer than pronotum, their dorsal and me- 

 dian areas sharply defined, dorsal margins strongly overlap- 

 ping, tips narrowly rounded or subacute; median carina of pro- 

 notum distinct only on metazona; furcula no longer than the 

 last dorsal segment, sometimes wanting. SERIES VII, p. 398. 



Series I. THE GRACILIS GROUP. 



Slender subcylindrical species of medium or small size and 

 grayish-brown hue, having the postocular dark stripe extending 1 

 back at least as far as metazona ; hind tibire green ; pronotum sub- 

 cylindrical, its disk slightly convex with sides subparallel, male, 

 feebly divergent, female, median carina percurrent, sometimes less 

 distinct on prozona than on metazona, the latter with hind margin 

 subtruncate or broadly obtuse-angulate ; prosternal spine short, 

 conical, the tip bluntly rounded; tegmina shorter than or sub- 

 equal to prouotum in length, either widely separated or slightly 

 overlapping, their tips broadly rounded; extremity of male ab- 

 domen feebly swollen ; furcula very short, cylindrical projections 

 or minute rounded lobes; cerci slender flattened plates, usually 

 obviously narrower at middle than at apex (PL III, r, c) ; sub- 

 genital plate small, distinctly narrower than long, with slightly 

 elevated, sometimes tuberculate extremity. 



KEY TO EASTERN SPECIES OF GRACILIS GROUP. 



a. Tegmina narrowly oblong, their dorsal margins widely separated: 

 hind femora green without dark cross-bars; hind margin of meta- 

 zona subtruncate and with a feeble median notch. 159. GRACILIS. 

 GO. Tegmina elliptical, slightly overlapping, male, feebly separated, fe- 

 male; hind femora dull yellow with two oblique brownish or fus- 

 cous cross-bars; hind margin of metazona obtusely angled or 

 broadly rounded without trace of emargination. Ki. VIRIIHPKS. 

 159. MELANOPLUS GRACILIS (Bruner), 1876, 124. Graceful Narrow-winged 

 Locust. 



Slender, subcylindrical, compressed, size small for the genus. Dull 

 ash or wood brown above, greenish-yellow beneath. Head greenish-yel- 



