98 Dr. F. A. Dixey on tJie phi/Iof/enetic 



evidently the last term in a series of dark spots which 

 forms a kind of inner border to the hind wing, there 

 being a separate oval or diamond-shaped spot for each 

 interspace between the nervules with the excep)tion of 

 the first two or three interspaces, in which the spots of 

 this series are fused together (fig. 24, IV., 10 — 15). In 

 Pijrameis atalanta the same blue-centred spot occurs in 

 the same situation, and here again it is easily seen to 

 be the last term m a series. But in Pyrameis atalanta 

 the blue colour is not confined to this last term, for in 

 most, if not all, specimens a definite area of blue, 

 varying from a few blue scales to a well-marked patch, 

 occupies the centre of the last spot but one. In the 

 hind wing of V. polycJdoros we recognise at once the 

 same submarginal series of spots, forming a complete 

 inner border to the wing, each spot being now crescentic 

 in outline, more or less fused with its neighbours, and 

 the blue centre being found not only in the last one or 

 two terms of the series, but in all of them except the 

 first. The inner portion of the border of the fore wing 

 in V. polychloros is formed by an evident continuation of 

 the same series, visible also in the fore wings of 

 P. cardui and atalanta (especially in P. cardid, under 

 side), but in these latter cases somewhat obscured by 

 the general coloration of the dark area of the wing. 

 The series as a whole is that which we have already 

 distinguished as IV., and the anterior portion of which 

 forms the external boundary of the light-coloured series 



D, a — (*■. The conspicuous blue centres of the marginal 

 spots in the hind wing of V. polychloros do not extend to 

 the remainder of the series in the fore wing ; neverthe- 

 less, in many specimens a few blue scales, quite incon- 

 spicuous, may be detected in the centres of IV., 5, 6 and 

 7. The same blue-centred chain of submarginal spots 

 is very plainly visible in A. levana, especially on the 

 upper surface. It occurs with great distinctness on the 

 under surface of A. pirorsa, and as a trace at the anal 

 angle of the hind wing on the upper surface of the same 

 insect, as also in P. gonerilla (fig. 25, IV., 15). Similar 

 traces will be found at the anal angle of the hind wing 

 in E. kefersteinii (best marked on under surface), and 



E. dione, in these cases the blue being reduced to a few 

 blue scales, almost invisible to the naked eye. If we 

 now turn to V, urtica, and notably to V. antiopa (fig. 26;, 



