96 Dr. F. A. Dixey on the phylogenetic 



reversion to, or survival of, an ancestral type) be carefully 

 examined, it will be seen that the arrangement of dark 

 spots and pale ground colour near the tip of the fore 

 wing closely corresponds with the pattern we have been 

 considering in the Vanessidce (figs. 21, 27; (/. figs. 1 — 4). 

 This correspondence is strikingly brought out in some 

 specimens by the creamy white colour of those pale areas 

 that answer in position to the dead white band and spots 

 in P. atalanta, the rest of the ground colour of the wing 

 in A, valesina tending to a dusky olive. 



The Vanessa-\ike character of this region of the fore 

 wing, which as we have just seen is perceptible enough 

 in the dark variety of A. papliia ? , becomes remarkably 

 vivid in the female of A. niphe; so much so, in fact, as to 

 give the latter insect almost the general aspect of a 

 Pyrameis, the underside especially suggesting that of P. 

 cardui.*- The resemblance does not depend only on the 

 special points which we are now considering, but also on 

 other features which will be noticed later. Confining 

 our attention for the present to the series D, a — ^, and 

 making a careful comparison between P. cardui, P. 

 atalanta ? and A. niphe ? , we shall not be able 

 to escape the conclusion that the series is exactly repre- 

 sented in this last insect, spot for spot (fig. 22). The 

 only apparent exception is l^, which is often absent from 

 the upper side of A. niphe ; on the under side, however, 

 ^ is distinct and conspicuous, and in at least one 

 specimen that I have seen (Hope Collection) it is 

 faintly visible on the upper side as well. The com- 

 parison of A. niphe 2 with other members of the 

 genus Argynnis makes it clear that these light-coloured 

 markings, which I have shown to be homologous with 

 the white spots of the Vanessidcs, are merely an accen- 

 tuation, as it were, of the general ground colour of the 

 wing between certain of the dark spots which are so 

 characteristic of the ArgynnidceA If any doubt remains 



■■'• The aspect of A. niphe ? is no doubt partly the result of its 

 mimicry of Danais clirysippus, but the special points named here 

 and below (p. 101) can scarcely be affected by this fact. Moreover 

 the resemblance as a whole is seen, on careful comparison with 

 other Argynnids, to depend on the retention and intensification of 

 true Argyunid characters, not (with the exception, perhaps, of the 

 general shape of the wings) on the acquisition of new ones. 



fThe spot a is in one resjiect exceptional, as will be seen later 

 (p. 101, note). It is to be observed also that the white spots in ^. niphe 



