one of the Locustidae) is described (30. Harris, Insects of New
England, 1842, p. 128.) as mounting on the upper branches of a tree,
and in the evening beginning his noisy babble, while rival notes issue
from the neighbouring trees, and the groves resound with the call of
Katy-did-she-did the live-long night. Mr. Bates, in speaking of the
European field-cricket (one of the Achetidae), says the male has been
observed to place himself in the evening at the entrance of his burrow,
and stridulate until a female approaches, when the louder notes are
succeeded by a more subdued tone, whilst the successful musician
caresses with his antennae the mate he has won. (31. The Naturalist
on the Amazons, vol. i. 1863, p. 252. Mr. Bates gives a very
interesting discussion on the gradations in the musical apparatus of
the three families. See also Westwood, Modern Classification of
Insects, vol. ii. pp. 445 and 453.) Dr. Scudder was able to excite one
of these insects to answer him, by rubbing on a file with a quill. (32.
Proceedings of the Boston Society of Natural History, vol. xi. April
1868.) In both sexes a remarkable auditory apparatus has been
discovered by Von Siebold, situated in the front legs. (33. Nouveau
Manuel d Anat. Comp. (French translat.), tom. 1, 1850, p. 567.)
[Fig.11. Gryllus campestris (from Landois). Right-hand figure, under
side of part of a wing-nervure, much magnified, showing the teeth, st.
Left-hand figure, upper surface of wing-cover, with the projecting,
smooth nervure, r, across which the teeth (st) are scraped.
Fig.12. Teeth of Nervure of Gryllus domesticus (from Landois).]
In the three Families the sounds are differently produced. In the males
of the Achetidae both wing-covers have the same apparatus; and this in
the field-cricket (see Gryllus campestris, Fig. 11) consists, as
described by Landois (34. Zeitschrift fur wissenschaft. Zoolog. B.
xvii. 1867, s. 117.), of from 131 to 138 sharp, transverse ridges or
teeth (st) on the under side of one of the nervures of the wing-cover.
This toothed nervure is rapidly scraped across a projecting, smooth,
hard nervure (r) on the upper surface of the opposite wing. First one
wing is rubbed over the other, and then the movement is reversed. Both
wings are raised a little at the same time, so as to increase the
resonance. In some species the wing-covers of the males are furnished
at the base with a talc-like plate. (35. Westwood, Modern
Classification of Insects, vol. i. p. 440.) I here give a drawing
314