The butterflies belonging to the genus _Amauris_ are among the most abundant and characteristic Danaine models of Africa. Some of the black and white species such as _A. niavius_ (Pl. VIII, fig. 6) are conspicuous insects in a cabinet. Others again, such as _A. echeria_ (Pl. VIII, fig. 7), are relatively sombre-looking forms. Among the best known mimics of the genus is a species of _Hypolimnas_[14]--_H. dubius_. This interesting form is polymorphic and mimics different species of _Amauris_. The variety _wahlbergi_, for example, is very like _A. niavius_, while _mima_ strongly resembles _A. echeria_ (Pl. VIII, figs. 8 and 9). It was at one time supposed that these two varieties of _Hypolimnas dubius_ were different species and the matter was only definitely settled when the two forms were bred from the eggs of the same female. Other mimics of _Amauris_ are found among the Papilios and the Nymphaline genus _Pseudacraea_. But among all the mimics of Danaines in Africa and elsewhere _Papilio dardanus_ is pre-eminent, and has been described by more than one writer as the most important case of mimicry in existence. Not only does it shew remarkable resemblances to various {31} Danaids, but it presents features of such peculiar interest that it must be considered in more detail. _Papilio dardanus_ in its various sub-races is spread over nearly all the African continent south of the Sahara. Over all this area the male, save for relatively small differences, remains unchanged--a lemon-yellow insect, tailed, and with black markings on fore and hind wings (Pl. VIII, fig. 1). The female, however, exhibits an extraordinary range of variation. In South Africa she appears in three guises, (1) the _cenea_ form resembling _Amauris echeria_, (2) the _hippocoon_ form like _Amauris niavius_, and (3) the _trophonius_ form which is a close mimic of the common _Danais chrysippus_[15]. Except that _cenea_ does not occur on the West Coast these three forms of female are found over almost all the great continental range of _dardanus_ and its geographical races. Northwards in the latitude of Victoria Nyanza occurs a distinct form of female, _planemoides_, which bears a remarkable resemblance to the common and distasteful _Planema poggei_, and is found only where the latter is abundant. All of these four forms are close mimics of a common Danaine or Acraeine model. Other forms of female, however, are known, of which two, _dionysus_ and _trimeni_, are sufficiently distinct and constant to have acquired special names. _Dionysus_ may be said to unite the fore wing of the _hippocoon_ form with the hind wing of the _trophonius_ form, except that the colour of the last part is yellow instead of {32} bright brown. It is a western form and is unlike any model. _Trimeni_ also is unlike any model but is of peculiar interest in that it is much more like the male with its pale creamy-yellow colour and the lesser development of black scales than occurs in most of