[87] See Moulton, J. C., Trans. Ent. Soc. London, 1909.
[88] In this connection it is of interest that a recent observer with considerable breeding experience finds that the dark doubledayaria variety of the Peppered Moth is more hardy than the typical form (cf. p. [101]). The swift success of the dark variety led some to regard it as better protected against bird enemies. It is, however, not unlikely that the deeper pigmentation is associated with some physiological difference which makes for greater hardiness. See Bowater, Journal of Genetics, vol. 3, 1914.
[89] As examples may be mentioned P. polytes, Hypolimnas misippus, H. dubius, and Pseudacraea hobleyi. With the exception of the planemoides form it is true also for P. dardanus, the most polymorphic of them all.
[90] Trans. Ent. Soc. Lond. 1909.
[91] Cf. F. G. Hopkins, Phil. Trans. Roy. Soc. 1895.
[92] Coloured representations of these two species will be found on Pl. 20 of Seitz, Macrolepidoptera of the World, Fauna Americana.
[93] Untersuchungen über die Mimikry, 1893.