76 PROCEEDINGS OF THE NATIONAL MUSEUM. VOL.XX. 



tance; furcula consisting of a pair of adjacent, obtusely angled, scarcely 

 projecting, small lobes; cerci long and slender, fully as long as the 

 supraaual plate, tapering not rapidly and on the basal half only, the 

 apical half slender, a little compressed, slightly arcuate, and feebly 

 downcurved apically; subapical tubercle of subgenital plate moderate, 

 suberect, as viewed from behind very bluntly conical. 



Length of body, male, 18 mm., female, 23 mm.; antennae, male, 7.25 

 inm., female, 7.8 mm.; teginina, male, 10 mm., female, 13 mm.; hind 

 femora, male, 9.5 mm., female, 12 mm. 



Nine males, 6 females. Yellowstone, Montana, October 9, 0. Y. Eiley 

 (U.S.N.M.); Sweetwater, Wyoming, Thomas (U.S.N.M., [No. 715]); 

 Wyoming, Morrison (U.S.N.M.); Newcastle, Weston County, Wyo- 

 ming (L. Bruncr); Gordon, Sheridan County, Nebraska, August (L. 

 Bruner); Explorations in the Upper Missouri and Yellowstone, F. Y. 

 Hay den. 



The species was originally reported from a between Eed Buttes and 

 Independence lioek, Wyoming, " but it has since been recorded by 

 Bruner (doubtless in some cases by mistake for some of the allied spe- 

 cies here first separated) from Garden City, Finney County, Kansas, 

 western Nebraska, Arizona, New Mexico, Montana and the Pacific 

 Coast. 



According to Bruner, this species in the Yellowstone region "only 

 feeds upon two species of plants, as nearly as I could ascertain by 

 observation, viz., the i pigweed' and a small greenish white plant of a 

 similar nature. Those found on the pigweed are somewhat glaucous 

 yellow, while those feeding on the other plant are more of a whitish 

 color, mingled with greenish blue instead of greenish yellow," the color 

 of the insects resembling to a considerable degree that of the plants 

 on which they feed. 



7. AEOLOPLUS PLAGOSUS. 



(Plate VI, fig. 1.) 



Pezotettix plagosus SCUDDER!, Ann. Rep. Chief Eng., 1876 (1877), p. 504; Can. 

 Eut., XII (1889), p. 75. 



Brownish yellow marked with dark brown or brownish fuscous; 

 especially noticeable is a dark medioclorsal stripe, extending from the 

 middle of the vertex between the eyes, where it is not half so broad 

 as the interspace, to or nearly to the posterior end of the pronotum, 

 broadening as it goes, on the posterior half of the pronotuin inclosing 

 a median pale line and fading out before the end of the metazona; 

 there is also a broad dark belt at the upper limit of the lateral lobes on 

 the prozona, extending forward to the eyes and fading inferiorly ; inter- 

 space between the eyes slightly broader than the frontal costa, the fas- 

 tigium broadly and rather shallowly sulcate, the frontal costa equal, 

 narrowly sulcate below the ocellus. Pronotum broadening slightly 

 posteriorly, the metazona punctate, the median carina distinct only 



