24 MR. H. J. ELWES ON THE GENUS PARNASsIus. [Jan. 19, 
1884, in hopes of being able to find larvee or pups, but was dis- 
appointed in this, as on other occasions, though I took many males 
and several freshly emerged females. One pair were taken in copula 
at about 11.30 a.m., but separated in the net, and the female pouch 
was developed and hard, leading me to suppose that it was not 
the copulation of a virgin female, or that the act was already complete 
when I found them. The males flew backwards and forwards over 
a space of about 200 yards by 40, where their food-plant was most 
abundant ; but unless chased flew at a slow pace, and frequently 
settled ; the females flew but seldom, and settled for several minutes 
at a time on the plants of Saxifraga. I did not observe them in the 
act of laying, though eggs were visible externally in one or more 
specimen. ‘The egg appears identical with that of P. smintheus, 
figured by Edwards in the ‘ Butterflies of North America.’ 
I returned to Brieg in May 1885, hoping to find the larva in the 
same place ; but in this season the snow was still unmelted on May 
26th, and lay two feet deep over the place where the butterfly had 
been common on July Ist in the previous season. This leads me to 
think that P. delius, like P. apollo and probably P. mnemosyne, passes 
some parts of its larval existence in the autumn, and remains 
dormant under the snow during 6 to 8 months, according to the 
elevation. I have found the butterfly as early as the end of June, 
both near Bergun and at Pontresina, and it may be found at 
higher altitudes up to 7000 or 8000 feet throughout July and 
August. 
The variation to which this species is subject consists principally 
in the number and size of the red ocelli. ‘he male has sometimes 
one, but usually two, red spots on the fore wing beyond the cell: 
the one on the costa is almost always present, and there is sometimes 
a black, and very rarely a red spot as well, near the middle of the 
hind margin of the fore wing. The fringe of the wings is sometimes 
plain white, and sometimes more or less distinetly marked with 
black at the end of the veins. 
In the variety intermedius, from the Altai Mountains, these black 
markings on the fringe are much more regular and constant. In 
female specimens, as in the American form smintheus, there are 
generally two, sometimes one, and rarely three, red spots beyond the 
cell. In one specimen in my collection, and in one figured by 
Meyer-Diur, these three spots are almost confluent, forming a short 
bar edged with black. 
The size of Swiss specimens varies from 2°50 to 1°80 inches ; the 
Altai specimens average abont 2°25; in American specimens the 
largest I have are of the so-called var. hermodur, from the Rocky 
Mountains of British Columbia, which are 2°40 to 2°50 inches across 
the wings, and the smallest, from Colorado, measure 2°10 to 1:80 
inches. ; 
With regard to the American form smintheus, such a full and 
excellent account of its habits has been given by Mr. W. H. Edwards 
in Butt. N. A. vol. i. pp. 21-26, that I need say but little; a 
further account of its habits as observed in the Judith Mountains, 
