CELASTRINA ARGI0LUS. 473 



angle of about 15° ; the club is curved very slightly upward. At more 

 complete rest, the forewings droop, bringing the costal edges of all the 

 wings together ; the body is then bent in such a way that, while the 

 abdomen and lower edges of all the wings rest upon the surface, the 

 thorax is elevated at an angle of 45°. The antennas are depressed so 

 that they are on a line with the outer half of the costal margin of the 

 forewings ; they divaricate, at the same time, at an angle of 80° or even 

 as much as 110°. The appearance of this sedentary species at irregular 

 periods in comparative abundance or rarity is very noticeable. In some 

 recent years it has been unusually abundant in both broods, over most 

 of the district it inhabits in England, e.g., in 1896, 1900 and 1901. In 

 1903, 1904 and 1905, the species was hardly seen over large areas, in 

 either brood, yet it was here and there locally abundant in both the 

 latter years. That this uncertainty in appeamnce is due to direct 

 climatological conditions, and that there appears to be no real founda- 

 tion for the supposition that has been expressed that these periods of 

 abundance and rarity take place in cycles, seem certain, for, after its 

 abundance in 1900, increased abundance in 1901, and the comparative 

 abundance of the first brood in 1902, scarcely a specimen was noticed 

 in the cold, sunless summer and autumn of 1902, and it was equally 

 scarce in both broods in the equally unfavourable season of 1903. 

 Moreover, it sometimes happens that the species only fails locally, e.g., 

 it was exceedingly rare in 1905 in Surrey, whilst not at all uncommon 

 in Essex. Bath notes the species as extremely abundant in Sutton 

 Park, in the spring of 1889, but exceedingly scarce in 1890, and he 

 attributes this scarcity to the almost complete failure of the holly- 

 bloom in 1889. Bankes states that, in most seasons, the insect occurs 

 sparingly in Dorset, that in other seasons it is hardly, if ever, seen. 

 Blachier also remarks (in litt.) concerning its appearance at Geneva, that 

 it is more abundant in some years than in others. 



Habitats. — On Strood Hill, between the playground of the old 

 school and the private garden of the adjoining house, a high wall 

 covered with ivy, was, between 1866 and 1871, the rendezvous of 

 bees and flies innumerable at the time that the ivy was in blossom. 

 Amongst these were three other visitors, Celastrina argiolm, Pyrameis 

 atalaiita and Aglais urticae. The "blue" was a source of never- 

 ending delight to one youngster, at least, and here he learned that 

 whilst the J s appeared to join the bees, flies and butterflies, in 

 extracting nectar from the expanded flowers, the ? s selected the 

 unopened heads for the purpose of egglaying. It is difficult to say 

 just how much those "azure blue " butterflies had to do with making 

 the writer a lepidopterist, but certainly some credit must be laid to 

 their account. The habitats of this species in Britain differ consider- 

 ably in spring and summer; in spring, the forests, woodlands, parks, 

 gardens, shrubberies, plantations and hedgesides where holly abounds, 

 are its chief haunts, while, in late summer, ivy-covered walls, 

 whether on ruined castles, old buildings, or in gardens, are 

 mostly selected for their restless, vapouring flight, for, in spite 

 of the large number of occasional food-plants, one suspects that, 

 in Britain at least, the early brood is confined largely to holly, 

 buckthorn and dogwood for its egg-laying, whilst ivy is almost 

 alone selected in the autumn. Distributed as the species is 

 throughout the whole PalaBarctic and Nearctic regions, circling the 



