male is testaceous and the female black with legs banded with red.
Other even more striking cases of inequality in size between the sexes
have been recorded ( Quarterly Journal of Science, July 1868, p. 429);
but I have not seen the original accounts.), and he is forced to be
extremely cautious in making his advances, as the female often carries
her coyness to a dangerous pitch. De Geer saw a male that in the midst
of his preparatory caresses was seized by the object of his attentions,
enveloped by her in a web and then devoured, a sight which, as he adds,
filled him with horror and indignation. (21. Kirby and Spence,
Introduction to Entomology, vol. i. 1818, p. 280.) The Rev. O.P.
Cambridge (22. Proceedings, Zoological Society, 1871, p. 621.)
accounts in the following manner for the extreme smallness of the male
in the genus Nephila. M. Vinson gives a graphic account of the agile
way in which the diminutive male escapes from the ferocity of the
female, by gliding about and playing hide and seek over her body and
along her gigantic limbs: in such a pursuit it is evident that the
chances of escape would be in favour of the smallest males, while the
larger ones would fall early victims; thus gradually a diminutive race
of males would be selected, until at last they would dwindle to the
smallest possible size compatible with the exercise of their generative
functions, in fact, probably to the size we now see them, i.e., so
small as to be a sort of parasite upon the female, and either beneath
her notice, or too agile and too small for her to catch without great
difficulty.
Westring has made the interesting discovery that the males of several
species of Theridion (23. Theridion (Asagena, Sund.) serratipes,
4-punctatum et guttatum; see Westring, in Kroyer, Naturhist.
Tidskrift, vol. iv. 1842-1843, p. 349; and vol. ii. 1846-1849, p. 342.
See, also, for other species, Araneae Suecicae, p. 184.) have the
power of making a stridulating sound, whilst the females are mute. The
apparatus consists of a serrated ridge at the base of the abdomen,
against which the hard hinder part of the thorax is rubbed; and of this
structure not a trace can be detected in the females. It deserves
notice that several writers, including the well-known arachnologist
Walckenaer, have declared that spiders are attracted by music. (24. Dr.
H.H. van Zouteveen, in his Dutch translation of this work (vol. i. p.
444), has collected several cases.) From the analogy of the Orthoptera
and Homoptera, to be described in the next chapter, we may feel almost
sure that the stridulation serves, as Westring also believes, to call
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