4J2 FAMILY VI. ACRIDID.E. THE LOCUSTS. 



gin with a submedian angulation (PI. IV, n, o) ; furcula 



distinct but very short. SERIES XIV, p. 433. 



jj. Size much larger, the males 27 or more mm. in length; cerci 



with apical half much enlarged, rarely (furcatus) forked. 



k. Disk of pronotum without light colored lateral stripes; 



furcula wholly wanting (PI. IV, p.) SERIES XV, p. 439. 



fcfc. Disk of pronotum with pale marginal lateral stripes; 



furcula present but very short (PI. IV, g.) 



SERIES XVI, p. 445. 



ii. Tegmina with distinct rounded fuscous spots; interval be- 

 tween mesosternal lobes of male subquadrate; lower face 

 of hind femora coral red ; front margin of pronotum slightly 

 flaring to receive the head. SERIES XVII, p. 450. 



Series VIII. THE ATLANIS GROUP. 



Species of medium size and grayish- or reddish-brown hue, hav- 

 ing the postocular dark stripe feebly developed, often subobsolete ; 

 antennae rather short, subequal in the sexes; occiput convex, 

 slightly raised above the level of pronotum, the latter with disk of 

 prozona transverse or quadrate, its sides parallel and rounded into 

 the lateral lobes, those of metazona somewhat divergent, with lat- 

 eral carinaB evident but vague; tegmina distinctly surpassing ab- 

 domen and tips of hind femora ; interspace between the mesoster- 

 nal lobes of male longer than broad, the niesosternum in front of 

 the lobes elevated to form a low, blunt conical tubercle ; hind tibiae 

 (in our eastern species) normally red, sometimes dull yellow or 

 glaucous ; supra-anal plate and furcula variable as to species ; cerci 

 broad, nearly straight, almost flat plates, one and a half, female, 

 to twice, male, as long as broad, the apical half but slightly nar- 

 rower than the basal one, generally through the oblique excision 

 of its ventral margin, the apex obliquely and broadly rounded. 



The Uta]iensis and frprctus Series of Scudder have been shown 

 by E. M. Walker (1000, 206) to merge, the species bntncrl, by rea- 

 son of its variable subgenital plate, forming the connecting link. 

 But two of the ten species of the two series recognized by Scudder 

 (1807) occur in our territory, the others inhabiting the Rocky 

 Mountain region or the Pacific slope. 



KEY TO EASTERN SPECIES OF ATLANIS GROUP. 



a. Median carina of pronotum percurrent, less distinct on prozona; apex 

 of subgenital plate strongly elevated above the lateral margins, its 

 tip either with a median notch or a subapical impression ; prosternal 

 spine appressed-conical, the tip bluntly rounded; lower face of hind 

 femora dull yellow. 192. BRUNERI. 



aa. Median carina of pronotum subobsolete on prozona; apex of subgeni- 

 tal plate feebly elevated, slightly thickened and with a shallow but 

 distinct median notch (Fig. 141, c); prosternal spine conical, usu- 

 ally distinctly tapering, the tip subacute; lower face of hind femora 

 pinkish-red or rosaceous. 193. ATLANIS. 



