THYMELICUS ACT.EON, AND OTHER LEPIDOPTERA. 245 



I was favoured with glorious sunshine, blue skies, and warmth — 

 favourable to day observation. Night collecting, of course, is 

 impossible in these days on the sea coast. 



The enormous profusion of certain common down species 

 was most striking. Pararge megcera and Melanargia galatea 

 were in thousands — the latter, especially the males, running 

 extremely small, compared with those encountered a fortnight 

 earlier on the Chilterns, where for the first time in my experience 

 I found this butterfly in some numbers. Indeed, I am happy 

 to think that galatea, which seemed to have become extinct 

 a few years ago on the Buckinghamshire chalk hills, has 

 recovered itself, and is again spreading in all directions in 

 suitable localities. But, while only the females were in good 

 condition when I was on the spot on July 13th, the Purbeck 

 galatea of both sexes were perfectly fresh, and remained so until 

 the day of my dejiarture. 



In sharp contrast to the Chiltern profusion, Agriades corijdon 

 on the Corfe and Swanage downs was few and far between — it 

 may be, again, not yet fully out. The few females met with and 

 turned back presented nothing in the way of variation ; and the 

 same may be said of Polyommatus icarus, which at this time, at all 

 events, was anything but the " Common " Blue. The males of 

 the latter species observed were generally much below the normal 

 size, the females displaying, also, less tendency to blueness 

 than those in Buckinghamshire. Plebeius cegon was evidently 

 over on the heaths between Corfe Castle and Wareham, but 

 I netted one perfectly fresh male on August 7th, among the 

 rough furze above the Lighthouse hear Tillywhim Caves. This 

 is rather a late date, I think ; and on the same day I observed 

 one very worn female Ciipido minimus at the same spot. When 

 I left Corfe A. bellargiis was just emerging. 



I see in the list of " Lepidoptera of the Isle of Purbeck " 

 ('Proc. Dorset. Nat. Hist., etc.. Club,' vol. vi, 1885) that 

 Drijas paphia is represented there by a single individual. On 

 August 11th I watched a couple of males flying round the privet 

 flowers by the roadside about a mile on the Wareham road. 

 Of Argynnis cydippe I saw nothing, nor does it appear to occur 

 in the Isle, and I only mention its absence in contrast again 

 to its sudden and abundant recurrence after many years in 1918 

 in certain haunts in the Chilterns, to which it has Ijeen stranger 

 for a long time past. On the same day about 10 a.m. (summer 

 time) the only specimen of Colias edusa — a male — seen this 

 year was flying on the slope of the down facing the railway just 

 outside Corfe Castle Station. Pieris brassicce was quite rare at 

 Corfe. 



The scarceness of Geometers was disappointing, especially 

 on the Swanage side ; nothing was really common, but I made 



