about as high as my head, where hundreds were around me, I observed the
females coming around the drumming males. He adds, this season (Aug.
1868) a dwarf pear-tree in my garden produced about fifty larvae of
Cic. pruinosa; and I several times noticed the females to alight near a
male while he was uttering his clanging notes. Fritz Muller writes to
me from S. Brazil that he has often listened to a musical contest
between two or three males of a species with a particularly loud voice,
seated at a considerable distance from each other: as soon as one had
finished his song, another immediately began, and then another. As
there is so much rivalry between the males, it is probable that the
females not only find them by their sounds, but that, like female
birds, they are excited or allured by the male with the most attractive
voice.
I have not heard of any well-marked cases of ornamental differences
between the sexes of the Homoptera. Mr. Douglas informs me that there
are three British species, in which the male is black or marked with
black bands, whilst the females are pale-coloured or obscure.
ORDER, ORTHOPTERA (CRICKETS AND GRASSHOPPERS).
The males in the three saltatorial families in this Order are
remarkable for their musical powers, namely the Achetidae or crickets,
the Locustidae for which there is no equivalent English name, and the
Acridiidae or grasshoppers. The stridulation produced by some of the
Locustidae is so loud that it can be heard during the night at the
distance of a mile (27. L. Guilding, Transactions of the Linnean
Society, vol. xv. p. 154.); and that made by certain species is not
unmusical even to the human ear, so that the Indians on the Amazons
keep them in wicker cages. All observers agree that the sounds serve
either to call or excite the mute females. With respect to the
migratory locusts of Russia, Korte has given (28. I state this on the
authority of Koppen, Uber die Heuschrecken in Sudrussland, 1866, p.
32, for I have in vain endeavoured to procure Korte s work.) an
interesting case of selection by the female of a male. The males of
this species (Pachytylus migratorius) whilst coupled with the female
stridulate from anger or jealousy, if approached by other males. The
house-cricket when surprised at night uses its voice to warn its
fellows. (29. Gilbert White, Natural History of Selborne, vol. ii.
1825, p. 262.) In North America the Katy-did (Platyphyllum concavum,
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