400 
IOLAUS. By Dr. C. Aurivillius. 
obscurus. 
bicaudatus. 
jordanus. 
glaucus. 
tajoracus. 
nursei. 
erlU. 
umjbrosus. 
I. obscurus sp. nov. is allied to the preceding species and above very much like it, but the colour 
is much darker blue. Beneath it deviates by the blackish-grey ground-colour with a violettish reflection and 
by the black markings; on the forewing a transverse streak at the cell-end and two transverse lines behind 
the cell-end are black; on the hindwing the basal transverse line is represented by some black streaks or spots, 
and the irregular discal transverse line is between the veins 2 and 1 b very fine or entirely interrupted; a black 
marginal spot in area 2. Both the specimens before me originate from Windhuk in the Damaraland and have 
been accessible to me by the kindness of the superintendent L. Peringuey. 
I. bicaudatus Auriv. (69 c) is similar to the preceding species, but it has differently shaped hindwings, 
being oblong triangularly extended at the anal angle, a still lighter blue colour of the upper surface, an almost 
unmarked under surface and a distinct transverse streak at the end of the discal cell of the foreAving. Another 
peculiarity is the absence of the mealy spot on the $ hindwing, or it may be scarcely traceable. Nigeria, in 
the district of Yola. 
I. jordanus Stgr. (Vol. I, t. 77 g). This species also occurs in Palestine and has therefore been des¬ 
cribed in Vol. I. Wings above blackish-grey, in the basal third more or less scaled blue; hindwing in the <$ 
with a distinctly prominent black mealy spot at the base of area 6; at the margin with a black anal spot and 
a black dot in 2, anal lobe and area 1 c at the margin with greenish scales. Under surface whitish-grey 
with two black transverse lines and on the forewing besides with a black transverse streak at the end of the 
discal cell; this transverse streak is absent on the hindwing; anal lobe black with green scales and connected 
with vein 1 a by a whitish yellow line; the black submarginal spot in area 2 is proximally bordered by a whitish 
yellow (creamy); some green scales in 1 c near the margin. Arabia. 
1. glaucus Btlr. is described according to a damaged specimen, but it is probably the same species 
as jordanus. The description runs as follows: ,,Most closely allied to I. belli ; forewing above blackish with a 
large, light violettish-blue basal and anal-marginal spot occupying about half of the wing; hindwing blackish- 
grey, lighter towards the proximal margin which is almost white; the centre of the wing is densely covered 
with bright violet scales, a submarginal row of spots which are proximally black, distally whitish; a black anal 
spot proximally scaled green and yellow and probably a similar spot between the small tails; fringes white; 
a velvety black spot of thickened scales at the base of the subcostal veins (veins 6 and 7); wings beneath 
white with two distinctly prominent transverse lines (the proximal one of the forewing interrupted at the 
veins) and the marginal line black; the transverse lines shaped as in belli ; the black, green and yellow anal 
spot larger than above; a small similar spot above the anal lobe. Somaliland: Duderi. 
I. tajoracus Wlk. has remained unknown to me; the type seems even in England to be no more available. 
The description says: ,,Expanse of wings: 1 inch 6 lines. Purple-blue. Forewing: a broad stripe at the costal 
margin, a broad marginal band and the apical third of the wing blackish-brown; a black transverse spot at the 
end of the discal cell. Hindwing: a large apical spot and an irregular marginal band blackish-brown; the marginal 
band is bordered with white and encloses at its middle a jet-black punctiform spot; proximal margin bluish- 
white. Under surface white; a transverse streak at the end of the discal cell and two somewhat dentate trans¬ 
verse lines in the marginal part blackish-brown. Hindwing: a narrow, undulate, blackish-brown band between 
the base and the transverse streak, and a fine, slanting blackish-brown line between this band and the base; 
the first distal transverse line forms a long and sharp angle near the proximal margin; the second distal trans¬ 
verse line is near the proximal margin interrupted and shortened, at the apex of the wing terminating into a 
spot; a jet-black punctiform spot as above; some metallic lustrous green scales between this punctiform spot 
and the anal angle. Head, thorax, legs and abdomen beneath white.” Tajora (Tadjura) on the north-eastern 
coast of Somaliland. 
1. nursei Btlr. (69 b, c) may perhaps coincide with tajoraca. Butler’s description does not quite 
exactly correspond with the figure: ,,Allied with I. umbrosa, the wings, however, above light smalt with two 
whitish dots above each other in the disc of the forewing near the slate-coloured marginal band; fringes of a 
purer white, towards the anal angle entirely white; hindwing above with 2 or 3 indistinctly defined, white 
discal dots in a row parallel to the margin; margin white, proximally bordered by a dark stripe which encloses 
the usual dark spots, and distally by the distinctly prominent black marginal line; fringes purely white with 
a grey line; wings beneath pearl-coloured with the same markings as in umbrosa, the transverse lines, however, 
blackish-brown instead of reddish. Arabia: Aden; Somaliland. — var. ertli Auriv. is beneath in the basal part 
darker; the blue colour of the hindwing above in the middle reaches to the costal margin and in 1 c to 4 to 
the black marginal line, entirely enclosing the black submarginal dots. German East Africa: Madibira. 
I. umbrosus Btlr. Wings above light violettish-blue; forewing at the costal margin, at the apex (very 
broad) and distal margin black, the blue colour covers the cell, the base of the area 2 (and 3) and the greatest 
part of the areas 1 a and 1 b; hindwing at the costal margin as far as vein 6 blackish, at the margin narrow 
whitish with black submarginal streaks and marginal line; anal lobe whitish with a black, green-scaled spot. 
