366 NORTH AMERICAN MELANOPLI (ORTHOPTERA) 



Though it is true that the size average optimum is reached in 

 this species at from 9000 to 10400 feet and that series from lower 

 elevations all average smaller, it is clear that conditions of im- 

 mediate environment often produce very great individual size 

 differences. 



Generally dark brown, in pale brown individuals often with 

 markings all recessive. A very dark postocular bar present but 

 extending caudad only to principal sulcus on pronotal lateral 

 lobes, this frequently flanked with buffy dorsad on occiput and 

 proximal portion of prozona, very rarely interrupted by an oblique 

 buffy fleck on the cephalic portion of the pronotal lateral lobes. 

 Occiput and pronotal disk sometimes weakly tinged with reddish, 

 sometimes with olivaceous. Tegmina the same, or occasionally 

 paler dorsad, or occasionally darker laterad and then sometimes 

 with flecks of paler there. Dorsal surface of abdomen buffy or 

 light reddish brown, the sides with dark areas which decrease in 

 size caudad. Cerci weakly and subgenital plate narrowly suffused 

 with brown at apices, this rarely extending to the lateral margins 

 of the latter and dorsal margins of the preceding sternite in 

 intensive individuals. Underparts buffy. Limbs individually 

 brown, reddish buff or buff; caudal femora with two broad oblique 

 bands and apices dark brown, the first band forming a V on the 

 external pagina and often fusing ventrad with the second band, 

 ventro-external margin and ventral surface buff or yellowish 

 tinged with dragons blood red internally (usual in series from 

 Paunsagunt Plateau) or dragons blood red with intervening 

 sulcus and basal and apical annulus yellowish or buff (in series 

 from Markagunt Plateau). Caudal tibiae usually rich glaucous, 

 rarely pale glaucous, but pink in pair from Red Canyon, seven 

 males and seven females from Bryce and two males and one 

 female from Cedar Breaks. Such dimorphism in the brachyp- 

 terous species of the genus is found only in some of the species of 

 a few groups. 11 



The present species is known from the following series of 

 seventy-seven specimens. 



Utah: Bryce, Paunsagunt Plateau, 8200 feet, VIII, 29 and 30, 1926, 

 (Rehn, Hebard and Farrar; series taken only after long search in Black Sage 

 and Antelope Brush, Purshia tridentata, on flat surface of plateau under 

 Western Yellow Pines, Pinus ponder osa), 16 cf, 15 9 , type, allotype, paratypes. 

 Red Canyon near western base of Paunsagunt Plateau, 6700 feet, VIII, 30, 



11 It will be probably found in olamentke Hebard of the present group and 

 is known in saltator Scudder and ascensus Scudder of the Saltator Group, 

 while dichromatism of a different character in the caudal tibiae occurs in a 

 number of species of the Femur-nigrum Group. 



