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Show 20 MR. H. J. ELWES ON THE GENUS PARNASSIUS. [Jan. 19, probably owing to the number of collectors, but in most of its habitats it is a common, and in many of them a very abundant insect. It commences to fly in some of the warmer valleys of the Alps in May ; I have taken it myself on May 25th on the Canton Wallis at about 2500 feet, but this is a local occurrence, as Meyer-Diir gives June 17 as the earliest date of its appearance, and on the same day I found half-grown larvae at the same elevation. It continues to fly for six weeks or two months, and fresh specimens may sometimes be met with up to the first week in August. I think that elevation has not so much to do with the time of its appearance as other circumstances. I found fresh specimens in the Lower Bregalia Valley near Chiavenna at 1200 feet in the end of June ; and six days later I found it close to Pontresina, in the Engadine, at nearly hOOO feet. It prefers warm rocky slopes facing south and west, and is rarely found in Switzerland on a north exposure, or in woods. Meyer-Diir says that it seems to be wanting on the " Urgebirge," and is only local on the " Molasse" formation. The flight of the insect is strong and sailing, but not rapid, and is continued from eight or nine in the morning till four or five in the afternoon. The females always appear in much smaller numbers than the male, fly less, and settle more often; with practice they may be distinguished on the wing. I am not aware that the insect has been bred in confinement from the egg, nor can I say with certainty whether the eggs are hatched in autumn or spring; but I believe that some part of the larval stage is passed in autumnl. The larvae feed up in spring on the young leaves of Sedum telephium and Sedum album, and go into the pupa stage about fourteen days previous to the appearance of the perfect insect. According to Reutti they feed only during sunshine, and I found them generally two or three together on hot rocks where the food-plant was abundant. When touched they curl up and unroll with strong convulsions, and if well grown and healthy will live two or three days in a closed box, as the larva and pupa were drawn by Miss F. Woolward from specimens which I sent alive by post from Brieg in Switzerland to England. I believe that the females in this species, as in others, are almost invariably mated very soon after their emergence from the pupa, as specimens in which the pouch is not developed are but seldom found. I am not able to say whether in a state of nature the eggs are laid on the food-plant or not, but, according to Mr. Thomson, this is not the case in confinement. The Rev. A. E. Eaton, in Ent. Mon. Mag. xix. p. 89, gives the following note on stridulation in the female of P. apollo:-" In the evening of July 23ru, whilst reclining on the grass near Bannio, Val Anzasca, a rustling as of a lizard or snake close to the back of 1 W. H. Edwards in 'Papilio,' vol. iii. p. 159, says:-" But G. M. Mollinger writes m e that the eggs of P. apollo, in Switzerland, hatch late in the fall, and the young larvas hybernate ; awaking in early spring, and eating the leaves of Sedum, not the flowers." |