THE LARGE BLUE 
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eyes are naked. (Under Side.) This has the ground colour 
pale greyish-buff, blending into light greenish-blue at the 
base. The fore wing has cream-white-ringed black spots 
distributed in a similar way to those on the upper side, but 
all are round. Usually there is an additional spot in the 
centre of the discoidal cell. The hind wing has all the spots 
black and ringed with white, three or sometimes four are 
basal, and there is an irregular row of eight beyond the middle. 
Female. (Upper Side.) The female is usually larger 
than the male and the markings are both larger and more 
numerous. On the fore wing the spots vary in number, 
frequently there are additional basal spots and as many as 
six or seven in the transverse series, which are sometimes 
confluent and much elongated into wedge-shaped markings. 
The median spots on the hind wing are also variable. (Under 
Side.) The under side of the female resembles the male, 
except that the ground colour is more ochreous, and the basal 
blue shading more tinged with green. Normally the markings 
are much larger than in the male, yet males occasionally occur 
marked like females, and females are sometimes marked like 
males. The blue of the female is usually rather brighter 
and more lustrous than that of the male. 
Life of Imago. The life of this butterfly is probably of 
short duration, not exceeding fifteen or sixteen days. 
Aberration. As far as the ground colouring goes, there are 
two distinct localised forms. Those occurring in Gloucester¬ 
shire are duller in colour, being a deeper violet-blue. Cornish 
specimens are brighter and lighter blue. The extinct North¬ 
amptonshire race was usually larger, darker in colour, and 
more heavily marked. 
The markings on the upper side are liable to much aberration. 
Occasionally the spots are obsolete in the male, except for a 
very small discoidal spot. From this extreme form every 
degree of development of the spotting occurs, to the opposi e 
extreme of large, more or less wedge-shaped maikings^. 
Females with obsolete markings are exceedingly rare, u 
vary greatly in the development of the spots on the upper 
side. The markings on the under side in both sexes are very 
constant, except for the small basal spot in the fore wing, w ic 
is often absent. Coalescence of the spots, so prevalent in 
