DRINA; BIDUANDA. By Dr. A. Seitz. 
987 
64. Genus: I^rlsia Nic. 
In the forewing the costal vein only ends far behind the cell-end, the 2nd subcostal brand) is equally 
distant from the base of the first branch and from the upper discoidal, the 3rd rises about midway between 
the cell-end and apex; the hind-margin of the forewing is somewhat concave. 4 conspicuously marked species 
are known extending from Indo-China to the Philippines. 
D. donina Hew. (= usira Fldr.) (160 a as clanina). Both sexes above brown, the $ with 2 rows of 
white spots in the marginal area. The white under surface is easily discernible from that of discophora (160 a) 
by the nebulous stripes, which are indicated before and in the marginal area of the hindwing, being both distinctly 
continued through the forewing as far as the costa. Burmah and Malacca. 
C. discophora Fldr. (159 h, 160 a) is similar to donina, but the is above quite deep dark blue except 
the margins of the wings and a large dark scent-spot in the cell, the shape of which resembles that of Hypolyc. 
phorbas ; the $ has also a violettish-blue reflection in the disc of the forewing, and the spots in the marginal 
area of the hindwing are covered with dark blue. Under surface of a pure white; in the forewing only feeble 
traces of submarginal streaks. Philippines. The species is rare; in the specimen figured by us the small tail of 
the hindwing was broken off. 
D. wavortia Hew. (146 B c, d) is very similar to discophora, but easily discernible by the lacking 
the scent-spot in the forewing. The under surface is more similar to that of donina. Of the spots on the hindwing 
in the $ only the anal ones are white. From Mindanao, taken in August till September near Davao, 
Lionga, and on the Agusan. 
D. maneia Heiv. (159 h). Beneath this species from Malacca is at once discernible from the preceding 
ones by the whole marginal area of the forewing being brown; the hindwing with a black band-spot before 
the base of the tail. The $ already approaches the $ form usually met with Cheritra, Hypolycaena, bein% above 
dark brown with white band-spots in the anal portion of the hindwing. The is above of a magnificent blue 
iridescence. 
D. ninoda Drc. has the usual colouring above, being brown with a white anal portion marked with a 
dull dark colour in the hindwing, but near its apex there are below the costa yet 2 white small spots. Under 
surface dingy white, in the marginal area, of the forewing 2 rather parallel nebulous stripes being defined on 
the middle median branch; in the hindwing a similar one in the marginal area and another stripe extending 
from the costa towards the liind-margin and enclosing the cell-end. Karen Hills. 
65. Genus: ISidiiamhii Dist. 
Easily recognizable by the under surface, where the hindwing in most of the forms is covered all over 
with often square or rectangular punctiform spots mostly arranged in 3 or 4 rows. Hindwing almost invariably 
with 3 tails, but the small upper tail is mostly smaller than the others. Subcostal vein of forewing with 4 branches. 
The <$ has mostly a highly developed scent-organ, so that the shape of the wings may be changed thereby and 
the hind-margin of the forewing convex. 
B. thesmia Hew. (159 d). The under surface is so characteristic that the figure renders it unmistakable. 
Forewing and apex of hindwing golden yellow; forewing with dull transverse markings, hindwing with rows of 
black spots. Above the are mostly quite brown, only the anal portion of the hindwing is narrowly whitish- 
blue with black spots. Our figure above exhibits in the disc of the forewing a large orange spot; this form flying 
together with the quite brown $$ has been denominated: minara Hew. (159 d, as thesmia <$, upper surface). 
Malacca and Sumatra. — fabricii Mr., from the Mergui Archipelago is beneath of a lighter ground-colour with 
paler markings; above with a red spot as minara-, I cannot tell whether the quite brown form has also been 
found there. — demialba Stgr. (159 d, e) exhibits in the $ the anal blue of the upper surface extending to the 
centre of the wing. Nias. — batunensis Fruhst. (159 e) is larger, the ^ similar to a very large demialba, but 
in the ^ the anal blue of the hindwing above is not half as broad as in demialba. Batu Is., Pullo-Tello. — 
umara Fruhst. (159 e) is discernible from batunensis by the absence of the yellowish-red discal spot which 
is only feebly noticeable in the <$ as a dull brown bronze lustre. From the Kina Balu. — The form depicta 
Fruhst. which flies together with umara on the Kina-Balu is beneath coffee-coloured instead of orange. 
above without a reddish-yellow discal spot. — vanica Fruhst. is another form from Borneo, but from the 
south of the island. The $ is above similar to both thesmia- and umara and has a narrow greyish-blue 
anal margin of the hindwing. Hindwing beneath more honey-coloured, almost without any white admix¬ 
ture; the subanal spots are lighter and more lustrous green. -— unicolor Stgr. is the Palawan form being above 
quite brown; on the under surface the orange colour is replaced by a dull reddish brown; this form is said also 
to occur in Borneo (Druce), but such Borneo specimens may be more correctly placed to depicta. — The 
imagines are fond of open spaces with high bushes, often playing in couples round the ends of the twigs and 
being easy to capture, though very delicate, too. 
donina. 
discophora. 
wavortia. 
maneia. 
ninoda. 
thesmia. 
minara. 
fabricii. 
demialba. 
batunensis. 
umara. 
depicta. 
vanica. 
unicolor. 
