SUBFAMILY III. LOCUSTIX.*}. 425 



Series XII. THE ANGU.STII'KX.MS GROUP. 



Medium sized species of slender form and grayish- or fuscous- 

 brown hue, having the piceous liar of prozona] lateral lobes nar- 

 row, often vague in female; disk of pronotum with sides subpar- 

 allel, male, feebly expanding' on metazona, female; median carina 

 distinct but low on metazona, subobsolete or wanting on prozona ; 

 tegmina fully develo])ed; prosternal s]>ine rather slender, subry- 

 lindrical, the apex obtusely pointed, male, usually stouter, sub- 

 conical, with apex very blunt, female; hind femora with outer face 

 usually tinged with fuscous, upper and inner faces with faint fus- 

 cous cross-bars ; hind tibife either glaucous or red in the same spe- 

 cies ; supra-anal plate as in Series key ; furcula and cerci variable 

 as to species; subgenital plate large, as broad as long, apex feebly 

 narrowed, but slightly if at all elevated, the median portion trun- 

 cate and impressed behind ; valves of ovipositor short, the lower 

 ones with tips decurved and basal tooth very blunt. 



Scudder ascribed to his Angustipennis Series four species, 

 which he separated in his key (1897, 136) only by the color of 

 hind tibijp, length of male furcula and degree of maculation of 

 tegmina, all extremely variable characters. Two of his species, 

 which he separated from the others only by the color of the hind 

 tibia?, are known to be dimorphic in this respect, and it is very 

 probable that three of his so-called species, viz., comptits, cocc-i- 

 iicipes and angustipennis, will in time be found to be only forms 

 of one widely distributed and variable species. Three of his nom- 

 inal species are known from the territory covered by this work. 

 One of them is, without doubt, a synonym of angustipennis. The 

 two which are sufficiently different to be included as valid may be 

 separated as follows: 



KEY TO EASTERN SPECIES OF THE ANGUSTIPEXNIS GROUP. 



a. Furcula more strongly divergent, subcylinclrical, less than one-third 

 as long as supra-anal plate (PL IV, m) ; tegmina often immaculate, 

 male, usually with obscure and feeble maculation along the median 

 area, female; smaller and more slender, length of body, male, 

 rarely over 22, or female, over 24 mm. 198. ANGUSTIPENNIS. 



aa. Furcula but slightly divergent, one-half as long as supra-anal plate; 

 tegmina with very distinct and rather prominent fuscous spots 

 along the median area; larger and stouter, length of body, male, 

 usually 24 or more, female, 25 or more mm. 199. IMPIGER. 



198. MELANOPLUS ANGUSTIPENNIS (Dodge), 1877, 111. Narrow-winged 

 Locust. 



Size medium, rather slender, the females but little the larger. Dark 

 grayish- or fuscous-brown, often with a reddish-brown tinge. Occiput and 

 disk of prozona fuscous; metazona and lower halves of lateral lobes paler. 



