ARICIA MEDON. 271 



is, I think, absolutely new for the species. I may say with a fair 

 amount of certainty, that I have found as many larvae of this insect 

 wild as anyone, and I have always found them attended by ants. . . . 

 I found an almost full-grown larva in May, with two ants upon its 

 back. They seemed to be moving their antennas up and down on 

 the back of the larva. Leaning too far forward, I disturbed the larva, 

 which dropped, and with it dropped the ants. That this contact with 

 ants is essential for the well-being of the larvae up to a certain point, 

 seems certain. We had larvae reared ab ovo, at exactly the same stage 

 as wild larvae discovered soon after leaving their hybernacula in April, 

 1905. Ants were purposely kept beside the latter, and away from the 

 majority of the former. A few of the former were also introduced near 

 the ants. The wild larvae (from ab. salmacis) and those from artaxerxes 

 kept in contact with the ants proceeded very satisfactorily. Those 

 reared away from the ants, remained small and always looked 

 unhealthy. In the end they died before pupating (Harrison). 



Foodplants. — Helianthemum vulgare (Buckler), Flrodinm cicutarium 

 (Zeller, etc.), scarlet geranium [Pelargonium] , in preference to 

 Helianthemum when provided with both (Wilson). In captivity, the 

 larvae feed well on any species of Helianthemum, any species of 

 Pelargonium, any species of Geranium, and upon Erodium. They 

 specially delight in half-decayed leaves of the zonal pelargoniums of 

 the greenhouse. If removed from any one food plant to another, they 

 feed without any hesitation upon the substitute (Harrison). 

 [Trifolium (Favre) suggested also as a possible foodplant by Hofner, 

 together with Cytisus, Lotus, Anthyllis, and other Papilionaceae, though 

 foodplants of several Lycaenids, require confirmation.] 



Parasites. — Apanteles astrarches, Marsh (Bignell) ; Microgaster sp. 

 (Logan). Large larvae at the beginning of the spring generally 

 produce seven or eight cocoons of one of the larger species of 

 Microgaster (Harrison). One larva was found to contain nine 

 hymenopterous (? chalcid) larvae (Chapman). 



Puparium. — Towards the end of May the fullfed larva spins about 

 the stems of Helianthemum, a few silk threads, near the ground. It 

 then spins a silken web on which to rest, and then a silken cincture, 

 which passes round the metathorax, and thus attached it rests in a 

 nearly perpendicular position, and so undergoes pupation (Tutt). In 

 captivity, however, the methods of pupation are far from being 

 uniform, as is shown by the following accounts : — W 7 hen the time of 

 pupation approaches the larva becomes of a paler green, and creeps 

 about restlessly, in order to seek a place for spinning. I laid crumpled 

 paper, gauze, dry elm and poplar leaves, and old Artemisia stems, 

 amongst the Erodium plants. As, however, with the larvae which first 

 became restless all this appeared of no avail, I shut up the two most 

 bleached and shrunk in a small wooden box, in which both gauze and 

 paper lay. Here they changed after five or six days (since eventually 

 they merely sat still) to pupae without spinning. The others in the 

 flower-pot changed on the earth, nearly free. I had almost come to 

 the conclusion that spinning in medon is altogether omitted ; however, 

 two spun up quite in the usual Lgcaena style, on a white silken web, 

 and with a thread round the body ; one of these was in the cavity of 

 an old elm leaf, the other on a willow leaf between stems of Artemisia, 

 which it had drawn together with some transverse threads, forming as 



