306 



BRITISH BUTTERFLIES. 



mens, examples with the spots much reduced or developed on the 

 upperside and with the blue tint brighter or greyer ; below, the normal 

 spotting is more or less accentuated, with the brown tint of the ground 

 colour ochreous or greyish, and the greenish-blue powdering more or 

 less extended from the base of the hindwings towards the middle. A 

 local race must therefore be judged from a series of individuals. Thus, 

 a series of liaurica compared with another series of avion from the 

 Pyrenees-orientales, will appear, when looked at in a general and com- 

 prehensive way, very distinct. Notwithstanding, amongst the avion 

 from Vernet, one will find examples of a lighter blue, furnished with 

 very large, very black spots, with an interneural row of whitish ocelli 

 pupilled with black along the border of the hindwings. These Pyrenean 

 avion would not appear out of place in a row of avion from Mentone or 

 Mt. Pacanaglia. However, the Pyrenean race is, speaking generally, 

 much darker." 



The variation in size in this species is very great, amounting to as 

 much as 20mm. The smallest $ in the Brit. Mus. coll., an English 

 one, has an expanse of only 30mm., whilst the largest ? , from the 

 Valais, measures 50mm. Amongst the British examples the smallest 

 $ measures 31mm. as against 42mm, which is the expanse of the 

 largest, while J .8 smallest $ , 30mm., as just mentioned, contrasts 

 almost as strongly w 7 ith the largest British $ with an expanse of 

 40mm. From this it will appear that the British race is somewhat 

 below the average in size, though the small specimens are comparatively 

 uncommon, the average size of the £ s from the general range of the 

 species being from 37mm. -44mm., and of the $ s from 40mm. -46mm. 

 The smallest specimens are from the Cotswoids, and the following- 

 quotation from the Trans. Ent. Soc. Lond. for 1877, p. xxiv., accords 

 with this : — " Mr. H. Goss exhibited a series of specimens of Lycaena 

 avion taken in the Cotswoids in June 1877. One-third of the speci- 

 mens exhibited were far below the average size, the remainder being 

 of the normal size. Both forms were taken flying together at the 

 same time of the year in the same locality. Mr. Goss stated that 

 according to his experience these dwarf specimens did not occur in the 

 same proportion in other parts of the country where the species was 

 taken. The specimens he had obtained in Devonshire and Northamp- 

 tonshire were, as a rule, of the average size." 



The range of spotting on the forewings on the upperside is greater 

 than was known to Borkhausen, though he is, of course, taking the 

 discoidal spot into his calculation, for this is sometimes the only 

 marking to be seen on this wing, and even this is occasionally wanting. 

 On the other hand the presence of the whole series of eight submedian 

 spots is exceedingly rare, but one, or even tw T o, basal spots on the 

 upperside of the forewing are not very scarce, especially in 

 English examples, while in some alpine and Oriental specimens 

 there are as many as three. In the submedian series, 3 or 4 in the S , 

 4-6 in the £ are the number of spots most commonly seen. The 

 hind wing is frequently unspotted, not even the discoidal spot always 

 occurring, but this is always traceable whenever two or more of the 

 median series are present. In size also the spots differ greatly, being 

 sometimes scarcely visible dots, and sometimes large elongated ovals or 

 pear-shaped dashes, so broad as to produce the appearance of a macular 

 band, always, however, divided by the nervures. The antemarginal series 



