158 PROCEEDINGS COTTESWOLD CLUB 1913 



hibernation. It was known that the eggs were laid on the 

 blossoms of the thyme, but all attempts to keep the young 

 larvae through the winter failed. The late Mr C. J. Watkins, 

 F.E.S., told me that in the seventies he spent many hours 

 in the spring crawling about amongst the thyme in its known 

 haunts, but could find no trace of a larva. My own experience 

 and that of other friends who joined in the search year after 

 year, was similar. 



I talked the matter over with the late Mr C. G. Barrett, 

 F.E.S., the author of " Barrett's British Lepidoptera," and he 

 suggested searching by day under the stones in the neigh- 

 bourhood of the plants of thyme frequented by the butter- 

 flies in the previous summer, but this method ended in failure. 

 A year or two ago, Dr T. A. Chapman, F.E.S., and Mr W. 

 B. Davis spent about a fortnight in the spring digging in and 

 around the thyme-covered ant-hills in a locahty near Stroud, 

 and still the search proved fruitless. I was unable to sub- 

 scribe to a friend's theory that the larvae spent the winter 

 up in the trees. In its Cornish locality, Mr Frohawk says 

 there are no trees. However, the honour of discovering the 

 larva of this interesting butterfly in its Cornish locahty (dis- 

 covered in 1 89 1 by Mr E. A. Waterhouse) is enjoyed by 

 Mr F. W. Frohawk, F.E.S., who pubhshed an excellent article 

 on it in " The Field," Christmas Number, for 1912, to which 

 the reader is referred. Cornish specimens are more brightly 

 coloured than the Cotteswold examples. The species appears 

 to be on the wing later in North Cornwall than on our hills, 

 owing, no doubt, to the locality being more exposed. Mr Fro- 

 hawk has sent me some beautiful specimens taken in July, 

 whereas my experience has been to find it very worn in that 

 month from contact with the long grasses which abound in its 

 favourite haunts. The discovery of the underground habits 

 of the larva during the winter, which it passes in the ants' 

 nests, apparently disposes of the theory that its extinction 

 in other localities has arisen from the practice of burning 

 the grass. If the roots of the grass do not suffer, it is fairly 

 safe to assume that a larva living amongst them would also 

 survive. 



