4O FURTHER RESEARCHES ON NORTH AMERICAN ACRIDIID^E. 



tain, in the extreme northwestern corner of that State. The past 

 season I traced it westward into Indian Territory and Oklahoma, 

 rinding it in similar rocky habitats. Specimens from Georgia and 

 Oklahoma differ so greatly in size, prominence of eyes, and other 

 minor characters that they would be separated as distinct species but 

 for the intergrades from Indian Territory and Arkansas. Oklahoma 

 examples are especially liable to be mistaken for vinculata, but the two 

 species can readily be distinguished in habitus, habitat, and habits. 



Saxatilis has been taken only on rock-surfaces, sometimes lichen- 

 crusted, sometimes bare and sun-scorched, either wholly unprotected 

 from sun and storm or amid a considerable growth of forest which has 

 sprung up since the station was colonized by the locust. Georgia 

 habitats are shown in my first report (Publication No. 18, Carnegie 

 Institution of Washington, pi. 2, figs, i, 2). In Arkansas it was com- 

 mon on Dardanelle Rock, on the rim rock at the edge of the summit 

 cliff of Magazine Mountain (pi. 4, fig. i), and at Wheeler's Fall at 

 Winslow. At Haileyville, Indian Territory, a few specimens were 

 secured on the summit outcrops of rocky ridges covered with deciduous 

 trees. In Oklahoma it was taken at Mountain Park on the rock slopes 

 of an outlying spur of the Wichita Mountains (pi. 7, fig. 2) and on the 

 ledges and boulders on the summit of Mount Sheridan (pi. 9, fig. i). 



In color and markings it so closely resembles the background of 

 its habitat as to be indistinguishable therefrom when at rest. Five 

 specimens are shown in plate i, fig. 2, and all would be practically 

 invisible but for the shadows cast by the late afternoon sun at the time 

 the photograph was taken. The ground coloration varies enormously, 

 in correspondence with the background, from deep fuscous, ranging 

 through various shades of brown and gray to nearly white. In the 

 Wichita Mountains it matches the flesh-color of the weathered granite. 

 The fuscous markings are usually strong, contrasting greatly with the 

 ground-color if that is pale, but aiding in concealment on the mottled 

 background. 



It is a sluggish, unsuspicious species, flying but a short distance 

 when disturbed, often with a distinct but relatively faint crepitation, 

 and is easily captured. In the past season specimens were first met on 

 Sand Mountain, Georgia, July 8. At this time adults of both sexes 

 were numerous, the males actively searching for and attentive to the 

 females, excitedly approaching them and fiddling with rapid vertical 

 movements of the closed hind legs, ranging in extent from 5 to 50 

 (sometimes even 90). Usually no sound was audible (to me) during 

 this act of stridulation, but occasionally I could catch a distinct and 

 rather pleasant "seep," resembling a bird-note at a distance rather 



