1910.] 215 



I do not know the evidence on which M. cynthia is believed to take two 

 years over its life-history, but I think the circumstances I here note go far to 

 corroborate that l^elief, if any corroboration be necessary. The small larva of 

 M. didyma rather surprised me ; it seemed an undiie elevation for that species, 

 and its small size suggests (with the M. cynthia facts before us) that it must 

 take two years (at 7000 feet) over its transformations. I did not keep the 

 larva, and so, not having bred it, may be in error ; but I am fairly well 

 acquainted with the larva of M. didyma, and know nothing else it could be. 



On July 21st P. callidice was flying on the Fiu-ka, and, under stones, its 

 empty pupa-cases were not uncommon, under two stones were respectively six 

 and seven empty cases, probably not all of one season. — T. A. Chapman^ Betula, 

 Eeigate : August 12th, 1910. 



P.S. August 13th. — I had just despatched the above note when I received 

 from Mr. Bethune-Baker, whom I accompanied on the Fiu-ka on July 21st, 

 a letter from Saas-Fee in which he says, " I am under the impression that the 

 former " {M. cynthia larvae) " freqiiently pass two winters in that condition, for 

 two or thi-ee will not feed, but are apparently lying up already, and that 

 although the heat at Baveno was very great." Mr. Bethrme-Baker has thus 

 done what I was blaming myself for omitting to do, viz., kept some of these 

 immature larvse under the observation necessary to confirm the conclusion 

 I had otherwise arrived at. — T. A. C. 



^„/ Agriades coridon and ants. — On June 19th I foiuid in the Rhone Valley, near 

 Fiesch, an abiuadance of H.i'pjyocreins coniosa, by the roadside, in isolated plants 

 and mixed with other vegetation. The day was stmless, but I may note, 

 parenthetically, that A. thetis was freely on the wing on the following day in 

 a neighbouring locality. It occiu-red to me to look for larvse of A. coridyon. 

 Searching vmder several dozen plants I met with three (3) larvaj. Then I came 

 across a fine plant, beneath and amongst which was much ants' nest material. 

 In this somewhat loose stuif I found eighteen (18) larvae; a smaller plant close 

 by, but on the same nest and with similar material excavated by the ants under 

 it, ailorded eight (8) larvae. I only happened to meet with another plant, a very 

 small, poor specimen, similarly on an ants' nest, this afforded no larva, and in 

 searching for other such plants I found luider ordinary plants one other larva 

 only. Imperfect as this observation is, it shows that ants and larvae flovirisli 

 together, and are mutually helpful, but it does not go far in deciding whether 

 all plants would have had as many larvse, had they also been on an ants' nest, 

 or whether the ants nested under a plant well supplied with larvae, whether the 

 butterflies laid more freely on the ant-protected plant, or whether, perchance, 

 the ants collected the larvaj, when small, from other plants. Two pvipse from 

 these larvae afforded Ichneiunons, emerging by cutting off a lid on August 7th 

 and 9th. These have been submitted to Mr. Morley, who says, it is an Ichneu- 

 mon sp., probably raptorius, Grrav., but both specimens being g g the determi- 

 nation cannot be quite certain. He adds that Marshall records the Braconid, 

 Apanteles impressus, from L. coridon. 



Tutt's " British Lepidoptera " reports no Hymenopterous parasite for A . 



coridon. — Id. 



S 2 



