16 PROCEEDINGS OF THE NATIONAL MUSEUM tol, no 



plate (fig. 10, w) with twin apices usually conspicuous, rarely poorly 

 differentiated. Aedeagus with dorsal valve well sclerotized and with 

 a narrow to rather wide marginal fold, anterior margin usually broadly 

 rounded, rarely with traces of sinuation such as in bilituratus defectus ; 

 accessory lobe of medium size for group; epiphallus with lophus 

 rarely showing anterior angulation in lateral view, and then poorly 

 developed, usually erect, in dorsal view the apex of lophus broad and 

 semitruncate (figs. 2,6,/; 3,e; 8,j,m). 



Female genitalia: Cercus (fig. 10,^) subtriangular, relatively 

 blunt; dorsal valve of ovipositor with "scoop" (fig. 10,n) moderately 

 rounded, the shoulder obtusely angular. 



Variation: The size of 11 representative males, measured in 

 millimeters, varies in pronotal length from 3.4 to 5.1 (av. 4.3), in 

 length of hind femur from 9.8 to 13.7 (av. 11.6), and in length of 

 tegmen from 15.0 to 25.0 (av. 21.1). Eight measured females vary 

 in pronotal length from 3.7 to 5.5 (av. 4.7), in length of hind femur 

 from 12.0 to 14.0 (av. 12.8), and in length of tegmen from 17.0 to 

 21.0 (av. 18.0). Eastern specimens average smaller than those from 

 the West. 



Tegminal length is decidedly variable. Unusually long-winged 

 specimens are occasionally encountered. Among them are a female 

 from Doniphan Co., Kans., Sept. 9, 1940, with tegmina reaching 

 9 mm. posterior to the hind femora, and two females taken in Fergus 

 Co., Mont., Aug. 16, 1940, with comparable measurements of 6.5 

 and 7.5 mm. A series of six females and two males was found dead 

 in a recently baited field at Fort Benton, Mont., July 14, 1940, by 

 Parker and Butcher. The average length of the tegmina extending 

 beyond the hind femora in the females of that series is 5.1 mm., with 



Explanation of Figure 2 



Lateral views of aedeagus, and {b only) dorsal view of aedeagus and epiphallus in natural 

 position within phallic complex. 



a, b: Melanoplus bruneri, Ft. McLeod, Alberta, Canada. 



c: M. mexicanus, Mt. Alvarez, Mexico. 



d: M. mexicanus, Guerrero, Mexico. 



e: M. bilituratus bilituratus. Placer Co., Calif. 



/; M. bilituratus bilituratus, Victoria, Vancouver Island, British Columbia, Canada. 



g: M. bilituratus, uncertain subspecific position, Guymon, Okla. 



h: M. bilituratus, uncertain subspecific position, 18 miles north of Alpine, Tex. 



i: M. bilituratus defectus, Mesilla Park, N. Mex. 



/; M. bilituratus vulturnus. Stone Mountain, Ga. 



k: M. devastator, lectotype. 



/; M. bilituratus defectus, Casa Grande, Ariz. 



m: Melanoplus sp., probably abnormal bilituratus vulturnus, Muscatine Co., Iowa. 



n: M. spretus, Nebraska. 



