﻿THE BUTTERFLIES OF THE BUCKS, CHILTERNS. 53 



preponderated, none of them approaching the form which we 

 have generally accepted as var. ceronus, Esp. 



9. A. corydon, Poda. The usual form of the Chilterns is 

 large, brilliant in colour, with deep black marginal borders on 

 the fore wings, though the narrow-bordered form is by no means 

 uncommon. In the males there are occasionally traces of 

 orange above the ocellations nearest to the anal angle of the 

 hind wings, as in ab. suavis, Schultz. The females display a 

 wide range of variation, from deep brown, without a trace of 

 blue scaling, to the extreme andromorphous ab. tithonus, Meig. 

 (= syngrapha, Kef.), the one and only example of which, taken 

 by me in Buckinghamshire on September 9th, 1913, is recorded 

 in the 'Entomologist' (vol. xliv. p. 290). Ab. semisyjigrapha, 

 Tutt, occurs very rarely. On September 12th, 1907, when 

 collecting with Miss Fountaiue, one or two were taken among 

 many intermediates ; this being a late season. The form ab. 

 albipimcta, Tutt, is also included in my series. Aberrations of 

 the under side in the female with confluent and asymmetrical 

 spots are not infrequent. I have also several ab. parisiensis, 

 Gerh., from the same spot. 



Locally abundant, it is generally to be found on all the north 

 and westward facing slopes, with a few stragglers coming over to 

 the south, but never beyond the chalk limit. 



Earliest seen, August 3rd, 1899 ; latest, September 13th, 

 1908. 



10. P. icarus, v. Kott. In warm summers there are usually 

 three distinct emergences, the females presenting many charming 

 forms, and, generally speaking, in the direction of decided male 

 coloration. Ab. tcarinus, Scriba, usually a few each year. 

 Following the diagnosis of the species made by Tutt in his 

 'British Butterflies,' I find the following female forms well 

 represented : — Ab. cceridescens, Wheeler, ab. semidara, Tutt, 

 ab. thestylis, Kirby. Besides which, I have ab. coeralea-angulata, 

 Tutt, and one interesting female taken in June, 1907 ; all the 

 wings pale lavender-blue. On the fore wings the orange spots 

 of the antemarginal band are obsolete, and the ground,^ colour 

 beneath pale whitish; in the same way the orange spots of 

 the hind wings are obsolescent. The "all brown" female is 

 decidedly rare. Mr. Warren reports an example of ab. arena, 

 Wheeler, August 9th, 1911; and I occasionally meet with the 

 ab. crassipuncta, Courv. 



Earliest seen, gen. vern., May 19th, 1900. I have an un- 

 usually early date in my diary, April 23rd, 1901, but I am not 

 sure from entry whether it relates to Bucks., or Middlesex. Gen. 

 ast, July 30th, 1899 ; gen. auctumn., September 6th, 1902 ; 

 latest seen, October 9th, 1913. 



11. P. medon, Hufn. [= agestis, Schiff.). Always a common 

 butterfly on the chalk downs; in favourable years first and 



