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NYMPHALIDAE 
to feed upon ; any puddle of filth it appreciates, as for 
example the drainings of farm sheds or cattle droppings. But 
it also has a decided taste for sweets, several having been 
taken from time to time on " sugared ” trees, and many 
have been caught while feeding on exuding sap of tree-trunks ; 
but I have never known this butterfly to be attracted by 
flowers. 
Distribution. In certain years A. iris is far more abundant 
and generally distributed over the country than in others, 
appearing in districts where it has not occurred for many 
years. It was unusually plentiful in 1868, 1881 and not 
uncommon in 1905 and 1911. 
The Purple Emperor occurs in most of the larger woods 
and forests in several counties of the southern half of England, 
from Lincolnshire to Herefordshire and Monmouthshire. It 
is unknown in Scotland and Ireland. Its range abroad 
extends through Central Europe, Amurland and China. 
Time of Appearance. The Purple Emperor is single brooded ; 
the normal time for its appearance is from about July 10th 
onward and throughout the greater part of August. 
Hibernation. Hibernation is passed in the larval state. It 
prepares itself for its winter's sleep by spinning a layer of 
silk on the stem of its food plant, usually at the fork of a 
branch, and rests in a straight position, lying on and closely 
adhering to the bed of silk. When a leaf is chosen, it spins 
a quantity of silk round the leaf stalk and stem, thus securing 
the leaf from falling, also a layer along the upper surface 
near the base where it settles down for hibernation towards 
the end of October, about the third week. The colour of 
the larva is then green, precisely the same hue as the upper 
surface of the leaf, but soon after settling down for its torpidity 
it gradually changes in colour, with the change of colour 
taking place in the decaying leaf. The green of the larva 
gradually becomes ochreous and finally a pale olive ground 
colour. The back is whitish-ochreous mottled with red ; 
the side stripes are lilac-pink, and the anal points reddish. 
The rough surface, composed of minute spines, gives it a 
downy appearance closely resembling the downy surface of 
the leaf. The colouring of both the larva and leaf, as well 
as the stem, are so similar that, whichever it chooses for its 
