12 CATALOGUE OF BUTTEKFLIES. 



two or more of the spots coalescing and forming a streak or 

 streaks. The females also are frequently considerably suffused 

 with the colour of the males on the upper wings. 



11. P. Argiolus (Linn.). Azure Blue. 



Polyommatus Argiolus. Staint. Man., vol. 1, p. 57. 



,, ,, Barrett'sLep.Brit.Is.vol. l,p.88. 



Lycoena ,, Kewm. Brit. Butt., p. 135. 



Larya. Buck., vol. 1, pi. xiv., fig. 1 ; Wils., pi. iv., fig. 13. 



This butterfly appears to have been tolerably common fifty 

 years ago in the county of Durham. It is one of the earliest 

 butterflies to emerge, appearing on the wing in May, or in 

 favourable seasons even in April. Mr. Wailes records tliat he 

 met with it once as early as the 18th April. He says (Cat., 

 p. 22), "It frequents woods and lanes where the holly grows, 

 upon which the larva feeds. It is nowhere more abundant than 

 around Bavensworth, where that beautiful evergreen occurs in 

 such luxuriance and abundance ; Gibside, Dilston, Winlaton 

 Mill, Darlington, and Shull. — William Backhouse, Esq." The 

 first three of these localities appear to be Mr. "Wailes' own 

 records. Mr. Backhouse's papers in my possession only give 

 "Darlington and Shull." Ornsby's Durham gives "Woods 

 and Lanes near Durham, Castle Eden Dene in May." Both 

 Mr. Maling and Mr. Hedworth repeat the localities I attribute 

 to Mr. Wailes, and add Chopwell. It is certainly much less 

 frequent now than formerly, and I never met with it myself. 

 The species is not in the Twizell list, and the only notice I can 

 find of it as a Nortliumberland insect is in the Entomologist's 

 Weekly Intelligencer, vol. IX., p. 103, where Mr. J. B. 

 Hodgkinson, speaking of Argiolus as a Cumberland species, 

 says, "It again appears in the adjoining county of IN'orthum- 

 berland in the limestone district, more frequently." Peeling 

 doubtful about this record I wrote to Mr. Hodgkinson on the 

 subject, and he informs me that it "must have been a misprint." 

 This is a very unsatisfactory explanation of the matter, but it 



