THE SWISS SPECIES OF THE GENUS HESPERIA. ? 125 
The Swiss species of the Genus Hesperia. (Plate iii.) 
By B. C. S. WARREN, F.E.S. 
(Concluded from p. 121.) 
H. onopordi, Rbr. 
"This interesting species occurs in several localities in the Rhone 
Valley, but I have only taken it between Branson and Follaterre ; 
where it flies in the meadows by the Rhone canal, at the former place ; 
and over a considerable part of the hillside at the latter. 
It is double-brooded and has the distinction of being the first 
Hesperia to appear in the spring and the last to disappear in the 
autumn; its only rival in this respect being armoricanus. In a 
normal year onopordi emerges in the middle of April, most of the other 
spring species not appearing before the end of the month. 
The first brood is a much shorter time on the wing than the 
second, and is usually over by May 20th; never, to my knowledge, 
surviving until June: the second, commencing in the middle of July, 
lasts to the end of September. The emergence of the second brood 
is more extended, which explains its long duration. I have taken 
single fresh examples with quite worn ones as late as September 2nd 
and 16th. Curiously enough, although the g's are just as abundant 
in both broods, the ?s ave extremely rare in the summer and autumn. 
Tn fact, I have only taken 2 ?s of the second brood, in the course of 
four seasons, though they are plentiful in the first. When I say 
‘plentiful,’ I do not mean they were in numbers likethe gs. Ihave 
only noted two species in which the number of the two sexes seem to 
be approximately equal; cacaliae and carthami; in the latter at 
Follaterre sometimes the ?s were more numerous than the gs. 
The distribution of onopordi in the Follaterre district is remark- 
able. At Branson it is confined to the water-meadows along the edge 
of the Rhone canal, where it never leaves the long grass. The 
collector who searches the neighbouring vineyards or road, will not 
find a single specimen. Yet goine towards Follaterre the small 
patches of uncultivated ground in and round the vineyards produce 
it, and just before getting to Follaterre it is found abundantly on a 
patch of bare and precipitous rocks. About a hundred yards beyond 
these rocks we find it again on the canal banks in company with such 
species as M. didyma, P. manni, A. lineola, etc., and many “ blues.” 
On the sandy hillside at Follaterre it flies over most of the lower parts, 
but only ascends about 400 ft. In these various habitats, some 
of which are of very considerable area, and others very restricted, the 
insect is confined to certain limits; though considering the diverse 
nature of the country within those limits, it seems remarkable that it 
does not occur everywhere on the right bank of the Rhone. 
I have always regarded onopordi as a lowland species, and was 
therefore much imterested and surprised when first I saw Mons. 
Oberthur’s record of the occurrence of var. conyzaeat Zermatt, the only 
other suggestion of an Alpine habitat for this species which I had noted 
being a single specimen in the collection of a friend, which was 
supposed to have come from Bérisal, many years ago. As it was only 
a single specimen out of a good number of Hesperiidae from the same 
locality, I was inclined to think it might have been taken a little above 
Brigue, and so got mixed with specimens from a little higher up; but 
JuLy, 1920. 
