TANAECIA. By H. Frcthstorfer. 
649 
I. 1913. 
vations of up to 2000 ft.; on Kina Balu up to 3800 ft. The majority of species prefer the shade of the open 
woods, where they may often be met with in great numbers, resting on low shrubs with wings expanded. Due 
to their feeble wings, their flight is never so rapid as in the true Euthaliidi, but they rather move ahead with 
a gentle up and down motion, generally returning to their old place. The centre of their distribution is the Macro- 
malayan Region, especially Borneo, with one species in the Andamans and threein the Philippines. Also in the 
Sulu Islands (Jolo) we find several species closely allied with the Borneo forms. The recognition of the various 
subspecies is one of the most difficult tasks confronting the Entomologist, and, considering the inconstancy and 
monotony of the markings which recur in all the species, it must always be a matter of sentiment rather and 
speculation than of certainty. This is particularly the case with the $$ which lack sexual differentiation. 
Beside this variability and analogy of markings, there exists a tendency toward colour-mutation which in cer¬ 
tain species (T. lutnla, apsarasa and pelea) produces all shades of colour from the palest to the most extreme 
melanotic. The variability in the colouring of individuals belonging to the same collective species is so great 
that even sceptic authors like De Niceville and Snellen considered as good species quite a number of mere 
forms which are here united on account of the similarity of their sexual organs; thus from Borneo alone 9 so- 
called species will have to disappear. But on the other hand it become necessary to establish a series of new, 
hitherto disregarded, insular forms. It appears to be the general rule, that of the three commonest Macroma- 
layan species there exist three main types, which are either a) altogether brown, b)^suffused with blue or 
violet, or c) distinctly margined with blue; these chief types are again connected with one "another by every 
possible intermediate combination of colours. Beside this variation in colour we find a great^dissimilarity in 
the shape of the black intranerval spots, which in one and the same species may vary individually from mere 
dots to large sagittate spots. These may be either isolated or united into undulate bands; and it is of importance 
whether the intramedian spots of the forewings are all alike, whether they are white or shaded with bluish- 
violet, whether they are isolated (T. lutala, apsarasa) or wheter they are united with'the j-uibmarginal band 
common to all the species ( T. pelea). On the hindwings it appears to be an important feature whether the" white 
area is traversed by two (pelea, lutala) or three rows of black or brown lunules (apsarasa). Every casual ob¬ 
server of this group would presumably suppose these forms to be in the majority crosses between different 
species. But the structure of the genitals presents just in those species which have the most similar colou¬ 
ring (lutala and apsarasa) such wide differences that hybridisation appears impossible, whereas vice versa spe¬ 
cies that are otherwise easy to distinguish from each other (T. pulasara and trigerta) have those organs almost 
identical, so that a copula would not be impossible. The variability of colouring is moreover accompanied 
by a great diversity as to the shape of the white bands which may be either narrow or very broad, and also 
to the contour of the wings, in each species there being found individuals with elongate, pointed’wings resem¬ 
bling Euthalia, as well as others with broader and more rounded outlines. Finally also their size is subject to 
great "variation, often depending on the locality; thus are f. i. specimens from ivestern Sumatra invariably lar¬ 
ger than those from the north-eastern part of that island. 
It is of some interest to observe that the Polymorphism of Tanaecia is limited to Borneo, the Malay 
Peninsula, Banka, Billiton and Sumatra with their satellite islands, whereas the remaining islands, particularly 
Java with its rigidly constant endemic forms, display a marked uniformity. Structurally Tanaecia differs from 
Euthalia in that on the hindwing the precostal is invariably bifurcate, and that the first two subcostal nervules 
confluesce with the main costal stem. In the frequently also the third subcostal unites with the costal 
vein to such a degree that only a short rest remains. 
a) Uncus, as far as examined, curved in sickle-shape. 
T. cibaritls Heiv. (131 d) is on account of its variegated, lovely under surface one of the prettiest butter- cilmritis. 
flies of the Andamans. Under surface of yellowish, of $ blue-green, the white band being accompanied 
on either side by a series of black streaks and lunules united into bands. In addition some conspicuous black 
submarginal lunules and, in the cell of the forewing, redbrown, blackringed dots. The <$<§ seem to vary accor¬ 
ding to the season, for Niceville as well as Moore figure specimens that do not agree with either Hewit- 
son’s type or our figure, having on the hindwing above the white band considerably narrower and margined 
distally by another, complete series of confluent undulate lunules of bluish violet. Beneath the white band of 
the forewings is likewise narrower, and on the hindwings the black spots accompanying the white band are hea¬ 
vier than in cibaritis. Such $$ I name vinaya form. nov. Andamans, according to Moore and Bingham also vinaya. 
NankaurUof the Nicobars, which latter locality Niceville however does not acknowledge; the ES represent 
the fa. vinaya, having in addition the hindwings margined with green. 
IX 
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