or to excite the female; and this is the first case known to me in the
ascending scale of the animal kingdom of sounds emitted for this
purpose. (25. Hilgendorf, however, has lately called attention to an
analogous structure in some of the higher crustaceans, which seems
adapted to produce sound; see Zoological Record, 1869, p. 603.)
CLASS, MYRIAPODA.
In neither of the two orders in this class, the millipedes and
centipedes, can I find any well-marked instances of such sexual
differences as more particularly concern us. In Glomeris limbata,
however, and perhaps in some few other species, the males differ
slightly in colour from the females; but this Glomeris is a highly
variable species. In the males of the Diplopoda, the legs belonging
either to one of the anterior or of the posterior segments of the body
are modified into prehensile hooks which serve to secure the female. In
some species of Iulus the tarsi of the male are furnished with
membranous suckers for the same purpose. As we shall see when we treat
of Insects, it is a much more unusual circumstance, that it is the
female in Lithobius, which is furnished with prehensile appendages at
the extremity of her body for holding the male. (26. Walckenaer et P.
Gervais, Hist. Nat. des Insectes: Apteres, tom. iv. 1847, pp. 17, 19,
68.)
CHAPTER X.
SECONDARY SEXUAL CHARACTERS OF INSECTS.
Diversified structures possessed by the males for seizing the
females Differences between the sexes, of which the meaning is not
understood Difference in size between the
sexes Thysanura Diptera Hemiptera Homoptera, musical powers possessed
by the males alone Orthoptera, musical instruments of the males, much
diversified in structure; pugnacity; colours Neuroptera, sexual
differences in colour Hymenoptera, pugnacity and odours Coleoptera,
colours; furnished with great horns, apparently as an ornament;
battles, stridulating organs generally common to both sexes.
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