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Sub-Genus — NOMIADES. 

 Ilubner. 



The species of this sub-genus differ from the next by the absence of any 

 red or fulvous spots on the underside. 



In Britain we possess four species, one of which, Alsus, belongs to the 

 sub-genus Pithecops, of Dr. Horsfield. 



POLYQMMATUS ARGIOLUS. 

 Azure Blue. 



Argiolus, Linn. Argi'olus, dimmintive of Argos, a city of Greece. 



This Blue has wings of a stronger texture than any other of the European 

 species, and is of entirely different habits, flying over the tops of, and settling 

 on, holly bushes, evergreen oaks, and ivy covered walls and trees, instead of 

 low growing plants, in meadows and on chalk downs. 



The male is of a pale blue on the upperside, slightly margined with black. 

 The spring brood of the female much resembles the male, but it has a broad 

 black hind-margin to the fore-wings, and black marginal dots on the hind- 

 wings. The summer brood has the hind-margins of the fore-wings still 

 broader; and the costa of the hind-wings also is broadly black. The under- 

 side is of a very silvery blue, with numerous black dots. The width across 

 the wings varies from one inch to one inch and a quarter. 



In Persia and the Island of Cyprus a variety, Hypoleuca, occurs, which 

 has no spots on the underside. 



There are two broods of the butterfly in the year. The first is on the wing 

 the middle of April, to the middle of May ; sometimes earlier, as the Rev. 

 W. Bree in "Loudon's Magazine" for 1831, mentions having seen it on 

 the wing as early as March 28th. The caterpillars from this are hatched 

 from the egg in the end of May, and feed on the flowers and young leaves of 

 holly, or young ivy leaves throughout the month of June. 



The second brood of butterflies appear in the end of July and in August. 

 The second brood of caterpillars feed in September and October, on the 

 flower buds and young leaves of the ivy ; and the winter is passed in the 

 chrysalis state. 



The egg is very much like that of the Common Blue, except that it is 

 rather larger, the shell is of a pale bluish green, and its whole surface, with 

 the exception of a central spot, is overlaid with raised white reticulations, 

 having little knobs at the angles. 



