154 
NYMPHALIDAE 
lived butterflies, its life often extending from the end of July 
into late spring following, or between ten and eleven months. 
Aberration. This species is liable to considerable aberration 
both in pattern and ground colour ; the latter varies from 
pale straw-yellow to deep red. Between these extremes the 
colour is of various shades and hues. A constant and 
recurring form has the ground colour a smoky-lilac, and of 
a semi-transparent appearance ; sometimes it only appears 
on one wing or in patches on all wings. Another recurrent 
aberration has the costal blotches confluent, forming one 
large black bar ; the two small central spots are eiiher very 
small or altogether absent, and the hind wings are purplish- 
black. This form is known as ab. ichnusoides. Another 
constant phase of aberration, known as ab. ichnusa , has the 
ground colour rich red and the two small black central spots 
and inner marginal blotch absent. Ab. polaris is generally 
of deep colouring with the central costal and inner marginal 
blotches united, forming a central black band across the fore 
wing. Sometimes the marginal bands are suffused and the 
blue spots entirely missing. Occasionally the second straw- 
yellow costal blotch is extended across the wing to the inneP 
marginal blotch and sometimes across the hind wing also. 
The blue lunules vary considerably in size ; very rarely they 
are much elongated into wedge-shaped markings extending 
across the black border, and in exceptional cases the apical 
white spot is replaced by blue. 
Genus NYMPH ALIS, Kluk , 1802 
THE LARGE TORTOISESHELL 
Nymphalis polychlorus (Linn., 1758). 
(Plate XII, facing page 161) 
Owing to the general similarity between the earlier stages 
and general habits, this handsome butterfly is more closely 
allied to the Camberwell Beauty than any other species. 
The eggs are of an ochreous colour and are deposited in a 
