OCR Text |
Show 1891.] FROM SOUTH-WESTERN AFRICA. 79 narrower, and their external black nervular indentations are very much shorter ; and from two to four of the minute white spots near the costa of the fore wings, immediately preceding the white band, are found on the upper as well as on the underside. A dwarfed specimen from Ehanda expands only 1 in. 8| lin. Genus PSEUDACR^EA, Westw. 31. PsEUDACRiEA POGGEI (Dewitz). 8. Hypolymnas poggei, Dewitz, Nov. Act. K. Leop.-Carol. Deutsch. Akad. Naturf. xii. p. 197, pi. xxvi. fig. 2 (1879). Omrora (August). One male example. This specimen agrees very nearly with Dewitz's figure of one of the two males stated to have been taken by Pogge in Central Angola, except that in the fore wings the subapical white bar is considerably narrower, and the greyish-white clouding of the apex on the underside is much more conspicuous. The thorax and abdomen are very imperfectly shown in the figure, the former being robust and (like Lhe head) very conspicuously white-spotted, and the latter, though very slender, bearing on each side six conspicuous spots, of which the first two are white and the rest ochreous-yellow. This most interesting butterfly is a very exact mimicker of Danais chrysippus; and it is especially noteworthy that in size (2 in. 10 lin. exp. al.) it corresponds with the smaller than usual D. chrysippus from tbe same locality. In three features it is even a closer imitator of its model than the female Diadema misippus, viz.: on the upperside of the fore wings the much narrower costal black and the absence of the apical white spot, and on the upperside of the hind wings the narrower, less diffuse, inwardly more sharply dentate hind-marginal black border. On the other hand, the greyish-white clouding on the underside of the apex of the fore wings and the conspicuous spotting of the abdomen are points which lessen D. poggei s likeness to D. chrysippus as compared to the colouring of the corresponding parts in D. misippus. These two characters and the subbasal hlack spots on the underside of the hind wings are retained generic features of Pseudacrcea, quite peculiar and unmistakable, and should, in conjunction with that of the very long and gradually clavate antennae, have prevented the error of the descriher of this butterfly in referring it to the genus Hypolimnas (-Diademu, auct.). P. poggei is very distinct from every other described species of Pseuducrceu. In the want of subbasal black spots on the fore wings it agrees with the P. lucretia group; but the abdominal spotting is like that of P. boisduvalii and P. trimenii. The rufous-ochreous ground-colour of the wings exactly accords with that of Danais chrysippus, and the paler tint of the hind wings is most perfectly reproduced; while on the underside the creamy ochre-yellow ground and the white neuration and black border of the hind wings (with also a general resemblance in the few white-edged black spots) are precisely simulative of the Danais. |