MORSE: ORTHOPTERA OF NEW ENGLAND. 495 
my largest series, in several different stages, was obtained in a 
raspberry thicket which had sprung up in a little clearing in the 
forest. Walker says that in Ontario it frequents the beaked 
hazel and arbor- vitae, and the southern variety has been reported 
from hemlock in Pennsylvania. 
The species is represented in New England, so far as known, 
only by the typical form with broad cerci. Both this and the 
southern variety with narrow cerci, P. g. variegata, are recorded 
from Ontario by Walker. The latter form was described from 
Ithaca, N. Y. I have found it common in the Catskill Moun- 
tains (Kaaterskill High Peak, 3800 ft.) and the southern Appala- 
chians (Grandfather Mt., Roan Mt., Balsam Mts., 3800 to 5500 
ft.). It has been reported also from Pennsylvania (Rehn et al.) 
and as far west as Minnesota (Somes) . This extended distribution 
of an entirely flightless boreal Locust, whose only practical 
means of dispersal is by its own unaided leaps, is of special inter- 
est in revealing the long period of time and the very gradual 
change of conditions during the withdrawal of the great ice-sheet 
from northeastern America. Not by extended flights of many 
miles at a time was the land in the wake of the retreating 
ice-sheet repeopled by this species, but by hopping, hopping, 
hopping, a foot or a yard at a time, pressing northward as the 
vegetation and circumstances permitted, clambering up the 
mountains as fast as the forest line advanced, dying out in the 
southern areas and on dry slopes as "the fatal sea of warmth 
filled the valleys below" and swept onward far to the north, 
until no\v such colonies as that on the summit of Ascutney Mt. 
are forever cut off from their kind. 
Purple-striped Locust; Purple-striped Green Locust. 
Hesperotettix brevipennis (Thomas). 
Fig. 87; Plate 11, figs. 1, 2; Plate 23, figs. 19, 20. 
Ommatolampis brevipennis Thomas, Bull. U. S. Geol. Surv. Terr., ser. 1, 
vol. 1, no. 2, p. 67 (1874). 
Hesperotettix brevipennis Scudder, Proc. U. S. Nat. Mus., vol. 20, p. 63, pi. 
5, fig. 2 (1897).— Morse, Psyche, vol. 8, p. 271 (1898).— Walden, Bull. 
Geol. Nat. Hist. Surv. Ct., no. 16, p. 110 (1911). 
Of small size and pleasing coloration, the female appearing 
rather stout owing to the brevity of the tegmina and wings. 
