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LYCAENIDAE 
or less striped with greenish. This remarkable change of 
colour is a wonderful instance of protective colouring, for 
the hue and markings exactly harmonise with the surroundings 
of the hibernating larva ; the dull lilac and greenish colouring 
produces a perfect obliterative combination of colour and 
renders the larva very inconspicuous on the decayed leaf. 
After hibernation and before again moulting, the larva 
gradually loses the lilac hue and reverts to the normal green. 
Like many other hibernating larvae frequenting marshy 
ground which frequently is liable to be flooded during the 
winter months, the Large Copper (ab. batavus) can survive 
immersion for a considerable time. It will stand a period of 
seventy or even eighty days' continuous immersion during 
hibernation. The pupal stage occupies about thirteen days. 
Imago. The following is a description of British specimens 
captured in the fens about a century ago. The average 
expanse of the wings in the male is 46 mm. ; in the female, 
49 mm. The sexual difference is remarkably distinct. 
Male. (Upper Side.) The ground colour is a rich coppery- 
orange, or flame colour; there are two black spots in the 
discoidal cell of the fore wing ; and the outer marginal border 
is black. The hind wing has a narrow black mark at the end 
of the cell; the marginal black border is dentated on the 
inner edge ; the inner margin is broadly blackish ; the fringes 
are whitish. (Under Side.) The under side of the fore wing 
is a rich deep orange ; there are three large rounded black 
spots encircled with white in the discoidal cell; beyond the 
middle is a transverse series of similar spots crossing the wing ; 
also a sub-marginal series of linear black markings bordering 
the outer pearl-grey marginal band. The hind wing is a 
silvery pearl-blue ; there is a broad outer marginal deep 
orange band with each edge spotted with black ; also a black 
marking at the end of the cell, and five black spots evenly 
distributed over the basal half of the wing, and nine others 
forming an irregular transverse series crossing the outer third 
of the wing ; there is a black spot at the anal angle. 
Female. (Upper Side.) The female is similar to the male in 
ground colour; the outer marginal band is broader ; the 
cell has three black spots, and there is a row of black spots 
similar to those on the under side. The hind wing is a blackish- 
