1886.] MR. H.J. ELWES ON THE GENUS PARNASSIUS. 1] 
in the allied genus Zuryades proved Von Siebold’s ideas to be in the 
main correct. 
Burmeister, in his ‘ Atlas de la République Argentine,’ Livr. J, 
p- 10, pl. 3, figures and describes the structure of the abdomen in 
Euryades duponcheli and E. corethrus, which is analogous to that 
in Parnassius. 
He says that the copulation in Zuryades 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 Rendus Ent. Soc. Belgique,’ vol. 18, 
p- lvi, says that he is convinced that the appendage of Furyades is 
an analogous structure with the pouch of Purnassius, 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 Huryades, 
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. He 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 observa- 
tions, as far as they went, were accurate, yet wishing not only to un- 
derstand more fully the manner in which the ponch 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 pupz 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 
