70 



forming a small natural coterie, e. g. minimus with sebrus and 

 lorquinii ; arion with areas, alcon, euphemus, etc. ; ■ astrarche 

 with eumedon, idas, psylorita, etc. 



As regards the distribution of our native species, Lampides 

 bceticiLs must be looked upon as an immigrant even in the 

 greater part of the south of Europe ; Everes argiades and 

 Celastrina argiolus are sedentary species throughout almost 

 the whole of the palsearctic and nearctic regions, the former 

 probably with a tendency to spread in seasons specially 

 suitable for it ; Cupido minimus and Plebeius argus {cBgon) are 

 spread over almost the whole continental part of the palse- 

 arctic region, the latter being represented in Japan by distinct 

 variations as in Europe, while Aricia astrarche has forms 

 spreading as far as India, and so on. 



Most of the species show considerable sexual dimorphism 

 in their coloration ; the development of the legs, the distribu- 

 tion of the colour, and the sizes of the two sexes are also often 

 very divergent. In most of the species much specialization 

 of scales takes place, "androconia" (plumules or battledore 

 scales) being present in all " blue " males, and long hair- 

 scales, abundant in some males, are almost entirely absent in 

 quite allied species. 



As regards egg-laying, very little is known of the natural 

 methods of the various species, although considerable advance 

 has been made during the last few years in describing and 

 photographing the ova of the commoner species. The length 

 of the egg-stage of all the British species of "blues" is, 

 however, quite well known. 



The larvai of all the species are more or less borers, and 

 consequently the neck is exceedingly developed. Seeds, 

 flowers, and leaves are attacked (varying with the species), 

 and the length of larval life varies very considerably in the 

 different species. 



The stage at which hibernation takes place is not the same 

 in all species. The larvae of Everes argiades and Cupido 

 minimus winter full-fed ; Polyommatiis icarus, Cyaniris semi- 

 argus, Agriades bcllavgus, Lyccena arion, and Aricia astrarche 

 winter in the third larval instar ; Celastrina argiolus and the 

 Nomiadids {Nomiades cyllarus and A^. melanops) hibernate as 

 pupae, and Plebeius argus (cBgon) and Agriades coridon as ova. 



The food-plants of the family are chiefly LeguminoscB, but 

 there are many exceptions. Celastrina argiolus and Lampides 

 boeticus have each almost thirty food-plants recorded. The 

 Aricias are essentially Geranium-feeders, though A . astrarche 

 also feeds on H elianthemum . The true Lycaenids, L. arion, 



