AGRIADES CORIDON. 97 



an elevation, being particularly abundant in the openings of the larch 

 forests, leading up to the Pointe de la Lauze, with Polyommatus hylas, 

 Hirsutina damon, Cyaniris semiare/us, Cupido minimus, Aricia astrarche, 

 Heodes virgaureae, etc., and extending far up towards the summit in 

 the region of Pamassius delins and Erebia glacialis, leaving most of its 

 congeners at the lower elevations. Similarly, it is as abundant all 

 around le Lautaret, leading up to the Col du Galibier, and swarms 

 throughout the whole length of the Veneon and Romanche valleys. 

 How different are these habitats again from its haunts on the cistus- 

 covered slopes of the Pont du Gard, the waste ground on the outskirts 

 of the wood that clothes the arbutus- clad hollows at the back of the 

 Castle hill at Hyeres, where it flies with Melitaea cinxia, M. phoebe, 

 etc. ; the lovely woodland dingles near Draguignan, whilst at Ste. 

 Maxime, apparently one of the earliest spots for the species in Europe, 

 it occurs in April in a thick pinewood, with no limestone near, and in 

 what one. might suppose was a most unlikely-looking place for the 

 species. Oberthur says (Etudes, xx., pp. 21-22) that, in early August, 

 A. coridon is extraordinarily abundant in the Hautes-Pyrenees, and, on 

 warm days, one sees large numbers on the road, resting or flying in 

 places where the torrents have wetted them. The species is also fond 

 of the excrement of horses and mules, and the large numbers that may 

 be seen on a single day on the road from Luz to Gedre often passes 

 imagination. Tasle observes (Ann. Ent. Soc. Fr., 1908, p. 689) 

 that "it is worthy of note that, in Morbihan, A. coridon, which is 

 never met with on the wing round Vannes, is found abundantly on 

 a little piece of land situated near Lantillac, beween Joscelin and 

 Locmine, where occurs one of these ' Pliocene islets,' of which a long 

 series extends en echelon from the extremity of Brittany to the gates 

 of Angers (Maine-et-Loire)." One wonders what the geological forma- 

 tion of these ' Pliocene islets ' is, and whether A. coridon occurs on all 

 of them, and is confined to them in this district. Constant states that, 

 in Saone-et-Loire, it is common in almost all localities on the chalk, 

 but is absolutely wanting on other formations. In Switzerland, it 

 is reported as very abundant everywhere, and certainly it seems to be 

 so in almost all the districts in which we have collected, except the 

 bogs above the Lake of Zurich, where it is apparently a scarce 

 wanderer from the surrounding districts. It reaches from the lowlands 

 to at least 8000ft. elevation, where suitable spots are to be found. 

 It is difficult to select characteristic habitats, but between Vevey and 

 Aigle it was the most abundant "blue," exceedingly common on a steep 

 rocky slope near Roche, where Polyommatus icarus and Cyaniris semi- 

 argus were also abundant, and Satyr us cordula, Hipparchia alcyone, 

 Melitaea didyma, and many other species abounded. It occurs in the 

 clearings among the larches by the side of the path leading from the 

 Col de laForclaz to the Glacier duTrient with Heodes virgaureae, Melitaea 

 dictynna, etc. The Val d'Herens may be taken as typical of any of the 

 lateral valleys of the Rhone, the insect occurring from the tangled 

 mass of flowers at the foot of the ascent just outside Sion, on the 

 slopes between this and Vex, in the meadows about Vex and Useigne, 

 on the borders of the woods that reach down to the road between 

 there and Evolene, then again on the upland slopes between Hauderes 

 and Arolla, until at last it is found equally abundant on the high 

 alpine pastures leading from Arolla almost to the summits of the 

 surrounding mountains. It occurs abundantly around the last pine- 



