LEPIDOPTERA. gr 



the surface of all the wings is uniformly deep brown ; the anal region has in both sexes, within 

 the extreme blackish boundary, a white thread, which encloses the anal appendage : underneath 

 the wings are grayish brown with a slight cupreous reflexion; the disk of each pair is marked 

 with a short oblique white streak, delicately bordered with brown, and intermediate between 

 this and the posterior margin, a saturated reddish-brown striga passes the surface of both pair, 

 being nearly straight in the anterior, and slightly interrupted in the hinder, until it approaches 

 the anal region, where it makes a sudden curve, becomes flexuose, and terminates near the mid- 

 dle of the interior margin ; it has a faint exterior edge of white, which, in the hinder pair, 

 increases in intensity to the anal region, where it is of a brilliant satin white, and accompanied 

 by a parallel interior striga of the same colour ; the anal appendage is entirely covered by a 

 round black spot ; an oblong spot of the same colour stands exteriorly of the tail, in a marginal 

 band of a more saturated tint than the ground colour, surrounded by a ferruginous ring, but 

 without a distinct iris ; a round group of white atoms occupies the space between this and the anal 

 appendage ; a brilliant white thread, commencing near the middle of the posterior margin, winds 

 along the anal region and appendage, being edged by the extreme brown fringe : body covered 

 with long delicate hairs, which are ferruginous brown above and grayish underneath; legs 

 banded alternately white and black ; tails black, tipt with white ; eyes with a pronounced white 

 edge posteriorly ; antenna annulated with white, the club being tipt with brown. 



It may be useful to bring into one point of view, the discriminating characters of the two last nearly 

 allied species, and to annex a few remarks on their history. I have satisfactorily identified the species 

 named Jarbas, by the comparison of a specimen in the Banksian cabinet, marked with a ticket in Fabricius 

 own hand-writing. The prior name of Jarbas, which the ticket bears, and which is also found in the 

 Mantissa Insectorum, where the insect was first described, has been exchanged in the Entomologia Syst. 

 Emendata, for the more classical name of Jarbas, which had been applied to another species. The speci- 

 men preserved in the Banksian cabinet is a male, from Siam, and accurately agrees with the individuals 

 collected by me in Java. The species named Xenophon by Fabricius is distinctly figured by Cramer with 

 the name of Melampus (PI. 362. G.H.), and less accurately by Donovan in his Indian insects. The authors 

 of the Encyclopedie, in the description of the Diurnal Lepidoptera (Hist. Nat. ix. 646), cite the figure 

 of Cramer in illustration of Jarbas, but according to the preceding statements it should be referred to 

 Xenophon. In all descriptions hitherto given which I have seen, one sex only is delineated : I am now 

 enabled to illustrate both sexes, and by that means, through the comparison of numerous specimens of each 

 species, exhibiting the modifications peculiar to the sexes, to remove the ambiguity remaining in systematic 

 writers regarding these two species. 



The peculiarities of Th. Jarbas are the following : it is at least one-fifth larger than Xenophon, the longi- 

 tudinal extent is also proportionally greater, and the general outline of the surface of the expanded insect 

 is more regularly triangular ; the ground colour of the upper surface, in the male, inclines to fulvous, the 

 exterior and posterior borders alone are brown, and the latter decreases gradually in breadth to the inner 

 apical angle ; the hinder wings are entirely without any black discoloration towards the base ; in the female a 

 saturated testaceous tint, with a slight cast of metallic yellow, extends uniformly over the surface, with a very 

 gradual increase of strength towards the margins. Several minute peculiarities of the under surface in each 

 species have been detailed in the preceding description ; and here I have only to note the brilliant orange lunule 

 over the exterior anal ocellus, which affords a permanent characteristic distinction to Jarbas. In Xenophon 

 the anterior wings are slightly rounded at the external apical angle ; the exterior margin has a very slight 

 sinuosity, which is too strongly expressed in Cramer's figure, and the general contour is somewhat broader 



than 



