PLATE XXVI. 
No.1—The Large Blue Butterfly (Polyommatus No. 6.—The Chalk-hill Blue Butterfly, showing the 
Arion). Under side. 
Bieae, We Femolecf the Large eae No. 7.—The Caterpillar of the Chalk-hill Blue Butter- 
No. 3.—The Large Blue Butterfly, showing the Under 
fly. 
side. - y ; 
No. 4.—The Chalk-hill Blue Butterfly. No. 8.—The Chrysalis of the Chalk-hill Blue Butter- 
No. 5.—The Female of the Chalk-hill Blue Butterfly. fly. 
PoLYOMMATUS ARION (the Large Blue, No.1). This is by far the largest and most splendid 
of the “ Blues,” as the blue section of the Lycenide are popularly termed by our collectors. It 
was at one time considered extremely rare, and by some scarcely believed to be a true British 
species. But several localities were subsequently discovered, in which it was found each season 
in some plenty, and the further discoveries of more recent lepidopterists have removed all 
doubts as to its being a native species. The spots on the wings of the male differ very consider- 
ably both in size and intensity of colour; the figure (No. 1) being taken from a specimen of 
medium strength in the marking. The Female (No. 2) is generally rather larger than the male, 
and has the spots and dark borders broader, but less strong in colour ; and the blue ground is 
of a duller tone. The under side (No. 3) has the ocellated spots larger, more regularly disposed, 
and more sharply defined than any other of the genus. 
The Caterpillar is unknown. 
The perfect insect appears in July, and the localities in which this entomological prize is 
said to have been taken are the following: the Mouse’s Pasture, near Bedford ; Dover Cliffs ; 
Marlborough Downs ; the hills near Bath ; Broomham Common, Bedfordshire ; near Winchester ; 
and in one or two localities in North Wales. But the most celebrated locality, and one in which 
it has been recently taken in some plenty, is Barnewell Wold, near Oundle, Northamptonshire, 
in which place the Rev. W. Bree states in a communication to the “ Zoologist” for 1852, that 
for several seasons previous to that year entomologists had visited the place, and captured many 
specimens, without seeming to diminish the annual supply. Since 1852, however, the continued 
pursuit appears to have grievously diminished the numbers of this beautiful imsect in this 
locality ; and we may therefore look forward to its becoming extinct in Barnewell Wold, as C. 
dispar has done in its once favourite fens of Cambridge and Huntingdon. In the year above 
named, however, the Rey. F. O. Morris informs us that on the 19th and 20th of July he took 
no less than eleven specimens. 
Polyommatus Corydon (the Chalk-hill Blue, No. 4). This species is the next in size to P. 
Arion, and if it were not so much more common, would be considered nearly as beautiful. The 
silvery-blue of the male (No. 4), just flushed with a tint of straw-colour, produces a peculiarly 
delicate effect, which is heightened by the dark border, becoming nearly black at the base of 
the fringe. The wings of the female (No. 5) are of rich brown, with a sharp touch of white 
near the centre of each ; and an ochreous border with black dots, both border and dots being 
much more conspicuous in the anterior wings than in the hinder pair. 
