THE CHALK-HILL BLUE. 155 



near Glastonbury, Somerset ; Downs near Marlborough, 

 Wiltshire Broomham, Bedfordshire ; near Bedford ; 

 near Winchester. 



THE CHALK-HILL BLUE. 



(Polyommatus Corydon.) (Plate XIY. fig. 2, Male ; 

 2 a, Female.) 



Colouring: Upper side, male, pale silvery greenish 

 blue, with very silky gloss, and shading off into a broad 

 black border. 



Female, dark smoky brown, with a leaden tinge, 

 sprinkled near the body with greenish blue scales of the 

 same colour as the males ; border of orange spots, more 

 or less visible. Under side marked as in fig. 2 a, on a 

 brown ground, with a row of red spots near border of 

 hind wing. 



The caterpillar (Plate I. fig. 10) is green, striped 

 with yellow on the back and sides. 



The chrysalis is brownish, and of the shape shown 

 at fig. 29, Plate I. 



The butterfly is out in July and August, frequenting 

 chalky downs, especially in the south, and where it 

 does occur is often extremely abundant. Occasionally 

 it is found off the chalk, having been seen in Epping 

 Forest, decidedly not a chalk district. Other localities 



