1886.] MR. H. J. ELWES ON THE GKNUS PARNASSIUS. 45 



As far as I have personally observed, it is found in meadows where 

 vegetation is rather rank ; and at Berisal, on the Simplon pass, where 

 it is most abundant at 4500 feet, the meadows where it flies have a 

 north aspect, while P. apollo confines itself to the hot slopes on the 

 other side of the ravine. 



With regard to its life-history little is known. Meyer-Diir says 

 that Kindermann discovered the apollo-Wke larva in April and 

 beginning of May on Corydalis halleri, and that it pupates under 

 fallen leaves in a strong web, the pupa being yellowish and like that 

 of the Zygaenidge. I have made several endeavours to discover the 

 larva myself without success, but I have strong doubts that Corydalis 

 is the only, if even it is the usual food-plant, for this reason, that it 

 is a spring flowering plant of very short duration ; whilst P. mnemo- 

 syne must be an autumn-feeding larva, as the insect flies in spring 

 or early summer very soon after the melting of the snow, and there 

 could be no time for the larvse to feed up after it melted. 



From observations made in Wallis, in June 1884, and again in 

 May 1885, I believe that the larva more probably feeds on an um- 

 belliferous plant (? Heracleutn, sp.), which was very abundant in the 

 places where the insect was numerous, and on which the females 

 often sat, whilst Oorydalis was either absent or withered at the 

 same date. Herr Bang-Haas thinks that in Denmark the larva is 

 a night-feeder, but knows nothing certainly about it. I was very 

 anxious to investigate the development of (he pouch in this species as 

 well as in P. apollo, and with this object visited WalUs in May 1885. 

 On May 24, 1 found the males abundant at about 3000 feet on the 

 south side of the valley, near Brieg, and caught several males and 

 fresh females, all of which had the pouch perfect. In the previous 

 year I found, a month later, at Berisal, that the males were worn, 

 and the females, though they were in two or three cases taken m 

 copula, had apparently been flying for some time, and had a perfect 

 pouch. After a good deal of searching I found a female fresh from 

 the pupa, at about 11 a.m., sitting on an umbelUferous plant, either 

 JEthusa or Eeracleum. I took her home and put her in a birdcage 

 covered with gauze at about 2 p.m., and at 2.30 one of the males 

 which had been fluttering round her for some time commenced 

 copulation. The female held on to a grass stem with the head up- 

 wards and the male hung to her with head down. At 2.45 the female 

 crawled up to the top of the cage, carrying the male with her; he made 

 no attempts to use his feet or hold on, and was supported entirely 

 by the abdomen. At intervals of a few minutes there were slight 

 movements of the abdomen of the male, but otherwise he remained 

 quite torpid till about 4 p.m., when the pair suddenly separated 

 without any appearance of a pouch on the female, whose abdomen 

 remained large and swollen as at first. At 6 p.m. there was not 

 the least change in her appearance ; she remained quietly holding on 

 to the gauze, whilst the male crawled about the cage. In the even- 

 ing I put another fresh caught male in, and on the following morn- 

 ing put the cage in the hot sunshine at 7-30 a.m. All three insects 

 fluttered and crawled about the cage for some time, but showed no 



