Ell OPALOCERA MALA YA XA . 



7 -a 



followed by two more obscure and much strmghtor f-t-* ^ , one submarginal and the other marginal. Posterior 

 wings with three ocelltited spots with white centres and whitish and black margins, the upper and largest 

 of which is siUaio Ih-Iwcou i\n>. subcostal uorvules, the second and smallest is placed between the lower 

 subcostal and dist:nid;il nervnli-s. and the third between the second and third median nervules. Both wings 

 have also a few whitish summons, and the anterior wings are shaded with dark brown beyond the apex of 

 the cell, and become more or less fuscous beneath the second median nervule; caudate prolongations 

 marked with white on each aide as above. The sexual tufts and margins of glands paler than whig. 

 Body and legs more or less cmu^lorous with wings. 



Female. Wings above pale brownish. Anterior wings becoming chocolate -brown beyond apex of 

 cell, and there possessing the following pale stramineous markings ; — a waved fascia commencing on costal 

 margin a little beyond cell and terminating above first median nervule, where it is outwardly followed by a 

 small spot; beneath are six spots placed three above and three beneath the Becond median nervule ; and 

 near apex there is also an indication of a pate spot. Posterior wings with the outer marginal area more or 

 less ochraceous, on which is a submarginal waved and broken dark chocolate fascia, becoming in some 

 specimens (as the one figured) obsolete towards anal angle ; on inner side of this ochraceous area is an 

 ill-denned darker apical patch or suffusion, ou which are three pale ochraceous spots, two above and one 

 beneath the diseoidal nervule; there 1b also a similar but much fainter spot beneath the first median 

 nervule (in one Malaccan specimen now before nn- 1 Ik-si- spots are nearly obsolete) ; anal caudate prolongation 

 marked with white on each side. Wings beneath generally as in male, but the smaller ocellated spot on 

 posterior wings in male absent, and the whitish suffusion more distinct. 



Exp. wings, S 90 to % millim. : ? 1 in to 1*20 millim. 



Bab, — Malay Peninsula; Province Wellesley (coll. Saiier) ; Malacca (Brit. Mus.) — Sumatra (Brit* 

 Mus.) — Borneo (coll. t'iodm. & Salv.l. 



Z. amethystm does not probably extend north of the Malay Peninsula, as here fainiistieally 

 treated, as from Tenaaserini a closely allied species has been described,* Considerable variation 

 in depth of coloration is observable both above and beneath amongst male specimens. 



This species atVonis a striking example of sexual dissimilarity in coloration ami markings, 

 in explanation of which several theories have been advanced, which are at least suggestive, if 

 not conclusive. As in this case, where dissimilarity exists, it is usually, though not invariably, 

 the male which is the most showy and brightly coloured, and Mr, Darwin considers that this is 

 due to t( sexual selection/' or, in other words, "the females for many generations having 

 chosen and paired with the more attractive males/* + and certainly much of the argument which 

 he applies to the sexes of the American genus Hjnntliti will apply to Zeuzhlia* It is probable, 

 at least on this view, that the female form represents more or less the ancestral type of the 

 genus, for not only are all the female forms of ZatzidUt with which I am acquainted coloured in 

 this manner, hut similar sexual IbrmB occur in the American genus Motpho, of which a striking 

 example is the PttpiliO mareits of Schaller, which, judging from the somewhat indifTeivut figure, 

 Mr.Kirby quite reasonably placed in the genus Zcuzidia, but which, by the acquisition of a 

 (ruianan specimen, I was subsequently enabled to show was the female sex of M or pko adonis t ^ and 

 almost simultaneously \Ton. C. Oberthur figured the closely allied female sex of Morpho 

 We have already alluded to the natural affinities of these genera, and the geological evidences 

 which minimise their present geographical estrangement, and when we observe that in each 



* Z. musom, Moore. 

 J Trans. EnL Soc. 1881, p. Sl>7. 

 September 30, 1882, 



f * Descent of Man,' 2nd edit. p. 818. 



§ 'Etudes d'eatomologie/ liv. Gme, t. vi. f. 1. 



t: 



