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 m. 8i lin. 



Genus Pseudacr.«a, Westw. 



31. PsEUDACRiEA POGGEI (Dcwitz). 



cj" . Hijpolymnas poygei, Dewitz, Nov. Act. K. Leo]).-L'arol. 

 Deutsch. Akad. Natnrf. xh. 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 under- 

 side is much more conspicuous. The thorax and abdomen are very 

 imperfectly shown in the figure, the former being robust and (like 

 ihe 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. e.ijK al.) it corresponds with tbe smaller than usual 

 D. chrysippus from the samu 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. pogge'Cs likeness to D. chrysippus as compared to the 

 colouring of the corresponding parts in D. misippus. These two 

 characters and the subbasal black 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 describer of this butterfly in referring it to the genus 

 Hypolimnas (^= Diadema, auct.). 



F. poggei is very distinct from every other described species of 

 PseudacrcBU. In the want ot 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. 



