FURTHER RESEARCHES ON NORTH AMERICAN ACRIDIID^. 4! 



than the note of an insect. The female made similar motions, but 

 less often and less energetically. 



When driven upon a background at variance in color with their 

 own, no uneasiness was exhibited, but after a time they crawled away. 

 Active in direct sunshine, they became sluggish when clouds obscured 

 the sun, and at this time were very easy to approach, allowing the hand 

 to come within 2 or 3 inches if it were advanced with caution. 



Trimcrotropis vinculata Scudder. 



Texas: Amarillo; Clarendon; Wichita Falls. 



A common species on the arid plains and westward. It is much 

 less conspicuous in flight than its associates, Spharagemon aequale, 

 Trimerotropis latifasciata , and Hadrotettix trifasciatus , owing to its nar- 

 rower wing-band, less deeply colored disks, and smaller size. 



Hadrotettix trifasciatus Say. 



Indian Territory: Caddo Hill; South McAlester. 



Texas: Quanah; Wichita Falls. 



Oklahoma: Mountain Park; base of Mount Sheridan. 



This handsome locust is one of the largest and most striking 

 species of the section of country examined. Owing to its wariness 

 and powerful flight it is a difficult insect to capture in numbers, though 

 it is not uncommon locally on bare or thinly grassed soil, along roads, 

 about washes and excavations, and in stony ground. At Caddo Hill 

 one of its stations was in an open woodland, but it is typically a crea- 

 ture of the treeless plains (pi. 5, fig. i ; pi. 6, fig. i). 

 Brachystola magna Girard. 

 Texas: Amarillo; Quanah. 

 Oklahoma: Cache. 



A huge and sluggish species, not uncommon locally on sun- 

 flowers and other tall weeds, clambering clumsily about or resting 

 quietly when undisturbed. Specimens kept alive over night were 

 observed to stridulate, apparently by elevating the tegmina and beat- 

 ing the wings against them. (Cf. Dictyophorus reticulates.) Both sexes 

 did this, but the sound produced by the female was much the fainter. 



Though commonly ranked as a geophilous desert species, in habits 

 and in the structure of the tarsi this is a purely phytophilous locust. 

 The form of the vertex of the head ; the variable, but often distinct 

 and sometimes conspicuous prosternal spine ; the presence of the ter- 

 minal spine of the outer row of the hind tibiae ; the form of the hind 

 femora, and of the subgenital plate of the male; the texture of the 

 surface of the body ; as well as the highly developed pulvilli and phy- 

 tophilous habit of life all seem to indicate the possibility of a closer 

 kinship with the Acridiinse than with the Oedipodinse. 



