PERONEA CRIST ANA, FAB., AND ITS ABERRATIONS. 261 



wingless forms or in the winged with brighter or variegated coloured 

 hind-legs in the males, and the females of the same species, since with 

 the provision to produce sounds, the males became less in need of the 

 bright colours on the hind-legs. 



Finally, the question why the hind-legs of grasshoppers only are 

 highly coloured, while in the locusts and crickets, that are so very 

 closely related to them, the bright colours on the hind-legs are not 

 developed at all, is readily solved, it seems to me, by the mode of life 

 of the representatives of the last two families. The fact is, grass- 

 lioppers are insects essentially diurnal ; they become most active 

 during the hottest part of the day ; duiing the identical time the 

 summoning sounds of the males are everywhere heard. The crickets, 

 on the contrary become active only at night. These are entirely, one 

 can say, nocturnal insects, and since bright colours are not distinguish- 

 able at night, their absence on the legs of crickets presents a readily 

 understood phenomenon. We can say almost the same about locusts 

 (Locustodea) although they cannot be considered wholly nocturnal 

 insects, owing to our lack of information concerning their habits. 

 Nevertheless, there is no doubt, that a considerable portion of the species 

 becomes active principally at night. Thus we know that locusts feed 

 almost entirely during the evening or night. It is also known that the 

 green locust (ijicm^ta viri(Ussi)na), for instance, begins its love walks 

 and serenades after sunset and continues them into the night. During 

 the day, however, this locust positively avoids sunshine. Another 

 species, Larusita caiitans, the best singer among the European represen- 

 tatives of its family, begins its stridulation also after sunset and 

 continues until sunrise. All these facts tell us that, if, at the present 

 time, we are not able to consider the locusts as purely nocturnal 

 insects, they were such most probably in the comparatively not remote 

 past. But if they come to the most active condition only at evening 

 and night, then the bright colours on their hind-legs could not 

 develop for sexual purposes, and this absence of bright colours had, in 

 its turn, a telling influence upon the mobility of the hind-legs in 

 locusts, which appear in them only as supports in the motion of the 

 insect and are deprived of those varied functions that are characteristic 

 of the hind-legs of grasshoppers. 



Peronea cristana, Fab., and its aberrations {inth plate). 



By J. A. CLARK, F.E.S. 

 {Continued fnim p. 229.) 



It will be observed that most (if not all) of the forms in division A 

 are referable to cristana and its vars., whilst in sect, a of division B, 

 although there are some undoubted aberrations of crista )ia, the greater 

 number of names mentioned are referable to hastiana and its aberra- 

 tions, or to other allied but distinct species. 



Desvignes, between 18-10 and 1845, captured some 1900 specimens 

 of the Peroneas in Whittlebury Forest. He expresses his doubts as to 

 the specific values of the various forms, and groups {Xoal., 1845, pp. 

 Hll et scq.) the Peroneas into two sections: 1. L'eriincaSjniria. 2. 

 I'ernnea-Vera. The latter consists of the various forms of 1'. cristana, 

 w liich he subdivides and describes as follows : 



A. Pcrunca uniculorcDui. — Yar. 1, iiiiirolorana, Dei. — Thia inject has generally 



