44 FURTHER RESEARCHES ON NORTH AMERICAN ACRIDIID.. 



thing definite will be known regarding the relations of the different 

 forms to which the rank of species is usually applied. It is very 

 probable that some so-called species are but forms of one which varies 

 greatly in color and structure. In New England the two forms known 

 as alutacea and rubiginosa seem to be constantly different structurally, 

 though rubiginosa has a color-variety resembling alutacea. South- 

 ward and westward the structural gap between the two seems to be 

 bridged, and both vary much in size, color, form, and proportion of 

 parts. It is highly probable that other groups of species in this genus 

 present an equal amount of variation. 



Hypochlora alba Dodge. 

 Indian Territory: Caddo. 

 Texas: Wichita Falls. 

 Oklahoma: Cache; Shawnee ; base of Mount Sheridan. 



Locally common on white sage (Artemisia sp.), in color exactly 

 matching the greenish-white tints of its background (pi. i, fig. i). It 

 prefers to escape observation by remaining quiet, but can leap well on 

 occasion. 



Campylacantha olivacea Scudder. 



Arkansas: Fayetteville ; Van Buren. 



Indian Territory: Haileyville ; Howe; South McAlester; Wilburton. 



Texas: Amarillo; Clarendon; Quanah; Wichita Falls. 



Oklahoma: Cache; Mountain Park; Shawnee; base of Mount Sheridan. 



This species, with its color-variety acutipennis, is a widely distrib- 

 uted and often locally very common locust, occurring among weeds 

 in fields, along fence-rows, and woodland edges. The green form very 

 greatly outnumbers the gray, though the latter is by no means uncom- 

 mon. It matures late, young being common until September, and 

 the adults even seem relatively soft-bodied and usually discolor to a 

 dull brown in drying. It is very sluggish, relying upon its protective 

 coloration, rather than activity, to escape destruction. 



Hesperotettix brevipennis Thomas. 

 Georgia: Sand Mountain. 

 Alabama: Cheaha Mountain; Lookout Mountain; Turnipseed's Ranch. 



This is the eastern representative, a near relative, and probably 

 the direct descendant of H. pratensis. Three males and a female were 

 captured. Of these a male from Sand Mountain presents an interest- 

 ing structural variation in the doubling of the subapical tubercle of 

 the subgenital plate through a bifurcation of its tip, a shallow' sulcus, 

 one-half as deep as wide, separating the two apices. 



