stag-beetle (Lucanus cervus), the males of which emerge from the pupal
state about a week before the other sex, so that several may often be
seen pursuing the same female. At this season they engage in fierce
conflicts. When Mr. A.H. Davis (69. Entomological Magazine, vol. i.
1833, p. 82. See also on the conflicts of this species, Kirby and
Spence, ibid. vol. iii. p. 314; and Westwood, ibid. vol. i. p. 187.)
enclosed two males with one female in a box, the larger male severely
pinched the smaller one, until he resigned his pretensions. A friend
informs me that when a boy he often put the males together to see them
fight, and he noticed that they were much bolder and fiercer than the
females, as with the higher animals. The males would seize hold of his
finger, if held in front of them, but not so the females, although they
have stronger jaws. The males of many of the Lucanidae, as well as of
the above-mentioned Leptorhynchus, are larger and more powerful insects
than the females. The two sexes of Lethrus cephalotes (one of the
Lamellicorns) inhabit the same burrow; and the male has larger
mandibles than the female. If, during the breeding-season, a strange
male attempts to enter the burrow, he is attacked; the female does not
remain passive, but closes the mouth of the burrow, and encourages her
mate by continually pushing him on from behind; and the battle lasts
until the aggressor is killed or runs away. (70. Quoted from Fischer,
in Dict. Class. d Hist. Nat. tom. x. p. 324.) The two sexes of
another Lamellicorn beetle, the Ateuchus cicatricosus, live in pairs,
and seem much attached to each other; the male excites the females to
roll the balls of dung in which the ova are deposited; and if she is
removed, he becomes much agitated. If the male is removed the female
ceases all work, and as M. Brulerie believes, would remain on the same
spot until she died. (71. Ann. Soc. Entomolog. France, 1866, as
quoted in Journal of Travel, by A. Murray, 1868, p. 135.)
[Fig. 24. Chiasognathus Grantii, reduced. Upper figure, male; lower
figure, female.]
The great mandibles of the male Lucanidae are extremely variable both
in size and structure, and in this respect resemble the horns on the
head and thorax of many male Lamellicorns and Staphylinidae. A perfect
series can be formed from the best-provided to the worst-provided or
degenerate males. Although the mandibles of the common stag-beetle, and
probably of many other species, are used as efficient weapons for
fighting, it is doubtful whether their great size can thus be accounted
329