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Show 1886.] MR. H. J. EI/WES ON THE GENUS PARNASSIUS. 11 in the allied genus Euryades proved Von Siebold's ideas to be in main correct. Burmeister, in his 'Atlas de la Republique Argentine,' Livr. ], p. 10, pi. 3, figures and describes the structure of the abdomen in Euryades duponcheli and E. corefhrus, which is analogous to that in Parnassius. He says that the copulation in Euryades is very protracted, and though he gives no details of the manner in which the appendages of the female are formed, yet he states that the secretion forming them proceeds from the male, in the same manner as in Parnassius. He does not, however, suggest any use for the appendages nor state whether there is any variation in them. From the figures it is clear that they are almost identical in the two species comprising the genus. Dr. Hagen, in the ' Comptes Rend us Ent. Soc. Belgique,' vol. 18, p. hi, says that he is convinced that the appendage of Euryades is an analogous structure with the pouch of Parnassius, and that the only difference is one of form, which may be easily understood if one allows that the fluid which composes it is emitted on the two sides during copulation. Burmeister, in Stett. ent. Zeit. 1874, p. 427, says of Euryades, that he is convinced that the female appendages of this genus are not developed before copulation, and that the substance of which the apparatus is composed is completely homogeneous with that of Parnassius. H e suggests that the secretion flows from the male during the act of copulation, and hardens afterwards in the form which it took during its exudation from the male's body. Though there was every reason to believe that Reutti's observations, as far as they went, were accurate, yet wishing not only to understand more fully the manner in which the pouch was formed, but also its function in the life of the insect, I went in 1884 and 1885 to the Alps to study the question, where the insects are abundant; but owing to various difficulties, which are detailed in my account of the life-history of P. apollo, delius, and mnemosyne, I failed in observing for myself the necessary details. I was, however, fortunate in procuring through Herr Heine, of Leipzig, a number of pupae of P. apollo, which were sent to the Insectarium of the Zoological Gardens, and have afforded ample details as to this species. Mr. Thomson's notes are here printed verbatim, but I was able to gather some further details which are worthy of note. He found that Parnassius apollo requires about an hour after emerging from the pupa, in order to perfect and harden the wings, and that the colour of these is at first of a yellowish tinge, but soon fades to white when exposed to the sun. This yellowish tinge I may add is found in some very fresh examples of almost all the species, and may be taken as an indication that the insect is only-just out of the pupa. He found that the copulation of the sexes takes place immediately after the complete development of the insects, provided that the sun is bright and warm, but that on dull days the insects remain |
