86 THE ENTOMOLOGIST’S RECORD. 
terms are convenient; so we continue to eall the form most prevalent 
in the lowlands the ‘ plain form”; even if we happen to find it, as I 
have done, at an altitude of over 6,000 ft. ! 
The differences between these two forms are too well known to need 
description. So far, in the lowlands, I have only come across 
serratulae once, at Eclépens; but it is known to occur in many other 
similar localities. I have seen one somewhat interesting note on the 
occurrence of serratulae at Branson. The late Mr. J. Alderson, in an 
account of a butterfly hunt in the Rhone Valley in 1910, recorded the 
capture of serratulae at Branson, on May 18th (Ent. Rec., vol. xxi., 
p. 185). In spite of frequent visits to that locality in May and June, 
during several consecutive seasons, I have never found serratulae there ; 
indeed, until I saw Mr. Alderson’s record, 1. felt sure that it did not 
occur there. Now, anybody who reads Mr. Alderson’s paper will notice 
at once that he gave more attention to the Hesperias than was usual ; 
therefore, I should have had no doubt that his identification was 
correct, and concluded that I had somehow missed the species; only 
the late Canon Favre records serratulae from Branson too (Wheeler, 
Butts. of Switz.), and gives the date July and August. This is quite 
impossible, and shows that Favre’s specimens were not serratulae; for 
in a locality such as Branson, June 15th would be a very late date for 
the species, and it is not double-brooded. Mr. Wheeler’s book is in 
general use among Enelish collectors, and one wonders if Mr. Alderson, 
having, possibly, some difficulty in identifying his captures of Hesperias, 
was not influenced by Favre’s record. It would be interesting to know 
if serratulae has ever been taken at Branson, or anywhere in the plain 
of the Rhone Valley ; possibly it has; but I feel more than doubtful, 
and cannot help thinking of armoricanus. 
Serratulae seems to have been chiefly regarded as a mountain 
species in the past; Kirby records it as inhabiting hilly and mountainous 
districts; and Kane says it is not found in the lowlands of Switzerland. 
We may conclude from this that it is much more widely distributed in 
the mountains; but where it does occur in the plains it is quite 
abundant. 
At Eclépens it appears about the middle of May, but seldom lasts 
more than three or four weeks; specimens taken in the beginning of 
June are usually not worth keeping. 
In the Alps I have found the species very common in the neigh- 
bourhood of Kandersteg, on the Gemmi Pass, and near Lenzerheide 
(Grisons), and less abundantly in many other localities. It shows a 
considerable range of variation, but seldom in a way which would be 
likely to obscure the identity of the specimen. Among the large 
number I have taken I find only one which would be at all trouble- 
some. In this specimen, the basal spots on the underside of the hind- 
wing are not of the formation characteristic of serratulae (i.e., more or 
less separated and rounded), but are practically united, and square in 
shape ; giving the insect a decided look of alveus. The other markings 
of the hindwing are, however, typical, therefore it was still possible to 
identify it without reference to the genitalia. (The latter were 
examined afterwards.) The median band of the underside hindwing is 
much less broad and more disconnected in serratulae than in alveus ; also, 
the former is, as a rule, a much smaller insect. In the plains of course 
there would be no question, as serratulae is over before alveus emerges ; 
