t>LE6ElUS AftGttS. 237 



is not easy to get a series of fresh ? s, for as soon as they emerge, 

 they are surrounded by swarms of $ s, and in a very short time are 

 knocked about and worn. The $ s fight, he adds, a good deal and 

 show wear and tear rapidly, particularly in the fringes. A $ and a 

 $ observed paired at Sus, were purposely disturbed, when the J 

 was noticed, in accordance with the habit of other " blue " 

 species, to carry the 2 . Gillmer states (Insekten Borne, xxiii., 

 p. 136) that, on July 14th, 1906, he accidentally observed the 

 courtship and pairing of a couple of Plebeius argus. Both insects 

 whirled round for a short time in the air, about two and a half feet 

 above the ground, and then, apparently wearied with their violent 

 flight, alighted on the ground on a dry twig beneath, of the thickness 

 of a lead pencil, and about a foot long. The $ alighted on the upper- 

 side of the twig, near its end, followed by the £ , and then, in con- 

 sequence of the crowding up of the $ , who was trying to reach the 

 side of the $ , went over on to the side of the twig. This was the 

 favourable moment for the 3 . He now ran beside the $ , back over 

 the greater part of the twig, and, much as the $ apparently tried to 

 avoid him, the $ had immediately caught the end of the abdomen 

 of the 2 with his clasps (harpagones), and the pairing was thereby 

 effected. This, therefore, occurred sideways, whilst the two insects 

 were moving along beside each other. After the lapse of a few 

 seconds, whilst the union between the two insects was becoming 

 secure, a change took place in their mutual position, when the $ 

 moved quickly round, and thereby took a position facing in the 

 opposite direction to the $ . So far as the observer could see, this 

 change was accomplished by the ? , since the $ had not altered the 

 direction in which he was facing, in consequence of the change. The 

 insects, unsettled after their change of position, then made, at the 

 instance of the 2 , some short excursions back over the twig, and 

 entirely in the direction of the $ , which dragged the $ a short 

 distance with her, so that he was obliged to walk backwards, after 

 which no change took place in their position. The whole occurrence 

 only lasted a few minutes, and took place in full sunshine. Before 

 the pairing was effected, both sexes had the wings partly open, but 

 sometimes closed for a short time, afterwards those of the ? were 

 closed, those of the $ sometimes half-opened. A gust of wind carried 

 the pair to a distance of some metres from their pairing place, when 

 the $ , so far as could be seen, carried the 2 '■< the pairing continued 

 unbroken. We have ourselves seen the species busily feeding at various 

 flowers, although it is not attracted so greatly as are some of its near 

 neighbours. We have seen it with Polyom matus icarus at the flowers of 

 Centaurea nigra at Cuxton,on flowers of lucerne at Bourg St. Maurice and 

 Gresy-sur-Aix, on blossoms of Calluna vulgaris in the Goschenen-Thal, 

 etc., whilst Gillmer observed it sitting in dozens on bramble-blossoms 

 in the Buchholz, at Schwerin, on July 21st, 1904. Gillmer notes (in 

 litt.) that, in Anhalt, the species is on the wing only in sunsbine, 

 resting quite immovably on dull days; it loves to bask in tbe sunshine, 

 expanding its wings to one-half or three-fourths, and moving the 

 hindwings under the forewings, at least in the $ . It usually rests 

 near the ground, on grass, heath, spurge, or dry branches of pine lying 

 on the ground. It is also attracted to flowers, and loves to suck the 

 nectar of the flowers of Polygala vulgaris. Its habit of resting 



