IOLAUS. By Dr. C. Aitrivillius. 
399 
Review of the 
I. Forewing with 12 veins. Hair-pencil of forewing beneath slaty-grey. Legs white without black spots. 
/. trimeni. 
II. Forewing with only 11 veins. 
A. Forewing beneath at the anal margin with a large hair-pencil. 
*. Hair-pencil yellow. 1 . scintillans. 
**. Hair-pencil white. /. mermis. 
***. Hair-pencil black or blackish. 
§. Wings beneath with an irregular, thick, brownish-red submarginal band being expanded to 
an apical spot at the apices of the wings. Anal lobe of hindwing above uni-coloured blue without 
red scales. /. creta. 
§§. Forewing beneath behind the middle with but one or two blackish or red transverse lines, 
f. Hindwing above in the areas 1 c and 2 without black submarginal dots. 
p. The light blue colour of the forewing above covers two thirds of the wing and reaches 
the costal margin; the black apex is scarcely more than 5 mm broad. Hindwing 
above blue as far as the costal margin. I. carina. 
pp. The blue colour of the forewing above rarely covers more than the basal half and does 
not reach the costal margin. Hindwing above at least at the apex of the costal margin 
black. 
+. The blue colour of the forewing above entirely or almost entirely covers the 
discal cell, reaches vein 4 and is distally more or less rounded off. 
o. Forewing above in the middle with a white spot. I. albomaculatus. 
oo. Forewing above without a white spot. 
1. The blue colour of the forewing above does not co\er half the area 3. 
a. Anal lobe of hindwing white with a black spot scaled green and without 
red scales or only with few such scales being almost covered by the 
hairing. 
a'. The lustrous grey surroundings of the mealy spot on the hindwing 
above are very extensive, covering the basal part of the areas 
4 to 6 and being at vein 5 only about 3 mm distant from the margin. 
Wings above light blue. I. iasis. 
b'. The lustrous grey surroundings of the mealy spot on the hindwing 
above are less extensive, extending hardly beyond the apex of 
the discal cell and being at vein 5 at least 5 mm distant from 
the margin. Wings above darker blue. I. sibella. 
b. Anal lobe of hindwing above broadly red with a black spot; the grey 
surroundings of its mealy spot of a moderate size and at vein 5 about 
6 mm distant from the margin. I. cytaeis. 
2. The blue colour of the forewing above covers the greatest part of the 
areas 2 and 3 and is at vein 3 only 2 mm distant from the margin. 
I. cottoni. 
+ +• The blue colour of the forewing above only covers the basal half of the discal 
cell and only reaches vein 2 or covers the innermost base of area 2 at most, 
o. The lustrous whitish-grey surroundings of the mealy spot on the hindwing 
above are very extensive, reaching the black marginal band in the areas 
5 and 6 and being there only 2 mm distant from the margin. Anal lobe of 
hindwing above proximally scaled red; wings above light blue. 
I. hemicyanus. 
oo. The blackish surroundings of the mealy spot on the hindwing above scarcely 
extends beyond the discal cell and is at vein 5 about 6 mm distant from 
the margin. Wings above deep blue. 
1. The first small tail (at vein 1 b) on the hindwing broad, about 9 mm 
long and above white. I. neavei. 
2. The first small tail of the hindwing shorter, above black with white 
fringes and only at the apex all white. I. agues. 
