Page:The Zoologist, 4th series, vol 1 (1897).djvu/549

Rh of our south coast. Thamnotrizon cinereus, L., may be often heard uttering a short sharp "tss, tss" in brambles and thickets before a shower of rain, or on a fine evening in the late summer and autumn; and it often chirps late into the night. The "Canadian Band," as the natives of the Dominion call the incessant chirping of insects after nightfall, is not heard in Britain, but in most countries, especially in the tropics, the sound is very loud, persistent and annoying. The chirp of the Cricket is well known, ana also possesses ventriloquial properties to a certain extent.

This power of stridulation, in the Saltatorial Orthoptera, is confined to the males, except in one curious family, the Ephippigeridæ, confined to the south of Europe and the north of Africa, in which the female is also capable of producing a sound when irritated or frightened. I have never heard any insect of this family perform, but should think that they are able to chirp very loudly. The elytra are abbreviated until they are quite rudimentary and useless for anything but musical purposes; the posterior part of the pronotum is raised, and seems to act as a sounding-board, as Darwin noticed (op. cit. p. 284). It was this form of the pronotum that suggested to Serville the name Ephippigera, from its resemblance to a saddle. One interesting effect of this power of stridulation among the Orthoptera is that it puts, or seems to put, a check upon a strong tendency to abortion of the organs of flight. The wings themselves are not affected, and in a large proportion of species are quite rudimentary. The elytra of the females are often much smaller than in the males, as their services are not required for musical purposes. But in the males, even if the wings are abortive and the elytra useless for flight, the basal part at least of the latter usually remains, sometimes very highly modified, for the purpose of performing stridulation. The comparative development of the organs of flight in the Orthoptera is such an inconstant character, that no species is based upon their abortion or perfect development. There are a large number of species in which the wings are abbreviated normally, and perfectly developed by aberration (perhaps atavism), and vice versâ. In our commonest Grasshopper, Stenobothrus parallelus, Zett., the wings are rudimentary, and in the females the elytra also; but in the males the latter are perfectly developed for stridulation; yet there is a rare variety in which the wings are perfectly developed. I possess a very curious and rare variety of the tiny Cricket, Tridactylus variegatus, Latr., with the wings perfectly developed and caudate, the typical form having entirely abbreviated organs of flight.— (Bellagio, East Grinstead).

Stridulation of Cicadidæ in Mashunuland.—You will observe that in accordance with your request I have paid special attention to the Cicadas, and very interesting insects I have found them to be. Personally I was much surprised and pleased to find so many different species in so limited