1886.] MR. H.J. ELWES ON THE GENUS PARNASSIUS. 27 
P. NOMION. 
Parnassius nomion, Fisch. de Waldh. Ent. Russ. ii. p. 242, pl. 6 
(1823-4). 
This species, though at first sight very like P. apollo, may be cer- 
tainly and constantly distinguished by the fringes of the wings, which 
are conspicuously chequered black and white ; whilst in P. apollo this 
is never the case to the same extent, though some specimens have 
a tendency to it. The pouch also (though of the same general form) 
is black, more lengthened behind, and set on at the end, and not 
underneath the abdomen; the antenne, the clothing of the body, 
and the general pattern of the markings are very similar. 
I am not aware that the geographical range of the two species any- 
where meets, P. nomion first appearing in the mountains of Dahuria, 
whilst P. apollo seems to go no farther east than the Altai Mountains ; 
but these ranges on the Siberian frontier are but little known. 
P. nomion appears to be common in the valley of the Amur, at 
Raddefskaia and Khabarofka, and Christoph found the larva feeding 
ona yellow-flowered Sedum near Vladivostock. According to Méné- 
tries P. nomion is found near Irkutsk and at Kiachta, and I have 
seen a specimen from this locality in Dr. Fixen’s collection. 
Bremer says that it is found on the north side of Lake Baikal on 
the Onon river, and on the Ussuri between Noor and the Ema; the 
largest and finest specimens are from the Bureija Mountains, and 
farther west they become smaller. 
M. Charles Oberthiir says in a letter that he has received P. nomion 
from the Abbé David, who found it in the mountains of North China ; 
he has also very curious specimens from Sidemiin Mantchuria taken 
by Jankowsky, which resemble the P. nomion of California, of which 
he has also an authentic specimen from the collection of Boisduval. 
This is probably the one mentioned by Boisduval in his list of the 
Butterflies of California. With regard to the occurrence of the species 
in N.W. America, there is, however, some doubt, for though Mr. H. 
Edwards says it has been taken in Alaska, and that he has seen a 
specimen in a collection from the Cariboo mining district in British 
Columbia, whilst Mr. W. H. Edwards includes it in his catalogue 
as from Alaska and Sitka (coll. Behr), yet I have never seen or 
heard of any true P. nomion in the numerous collections made in the 
Rocky Mountains of late years. 
I have, however, a female specimen of P. smintheus, var. sayi, 
which might very well be considered as a small form of nomion, and 
I am not able to find any good character by which to separate it. 
Indeed, it is quite possible that P. nomion represents P. smintheus 
on the North-western coasts of America, and that Mr. Reakirt’s idea, 
cf. supra, that they have sprung from the same stock, is a 
correct view, though it would be a very curious fact in distribution if 
it was found that the two species come together in N.W. America, 
whilst in North-east Asia, as far as one can judge, from the very 
scanty materials which exist, P. nomion and P, delius remain distinct. 
P. nomion varies considerably, but not so much as some species of 
