175 
THE CHALK-HILL BLUE BUTTERFLY. 
Papilio Corydon. 
PLATE XXXII. 
Papilio Corydon, Donovan's Brit. Insects, pl. 236.—Hesperia 
Corydon, Fabricius, Ento, Syst. iii. 
Tue whole upper surface of the wings and body of 
this butterfly are of a pale silvery blue, with a 
broad, black, fringed margin; that of the lower 
wings with a row of central equidistant blue rings, 
or eye-like spots. The under surface of the insect 
is of a grayish brown, with a black margin, having 
a double row of white spots in the centre. All the 
other parts of the wings are ocellated. 
Thisis an exceedingly local British butterfly, and 
has only been found on the Chalk Hills, between 
Dartford and Rochester, particularly on a long range 
of hillocks, leading from Dartford to the wood of 
Darent-Home. This butterfly has been called the 
Chalk-Hill Blue Butterfly, from the locality where 
it hasbeen found. We believe it has not heen detected 
in any other part near London. The larva is un- 
known. It appears in its winged state in the first 
and second week of July. 
The female is brown above, with sometimes a 
slight tinge of blue near the base of the wings, edged 
with yellow spots; under side generally darker 
than the male, and the spots more distant. 
