222 [October, 



mountains on either side of these plains without undergoing much 

 modification. In speaking of the flora, M. Eugene Trutat, in a recent 

 work on the Pyrenees, states that, " we may learn from palaeontology 

 that the species have varied but slightly since the Glacial Epoch, 

 though their distribution has been profoundly modified ;" and where 

 we find very distinct species, what he calls, " especes de premier 

 ordre," in the Alps and Pyrenees, they have probably not arisen since 

 this period, but the conditions have been favourable to their survival 

 in the one locality and not in the other. The interesting Pyrenean 

 varieties of well known alpine species belong to quite a different 

 category, and are only such as might be expected to arise in regions 

 at present so isolated, and offering somewhat different conditions of 

 climate. It has been stated that there is a far larger proportion of 

 peculiar species among the plants, but the flora should be compared 

 with the fauna as a whole, and not with a single zoological group, as 

 the Lepidoptera. Besides which species are occasionally founded by 

 botanists on distinctions that would hardly hold good with Lepidoptera. 

 For example, M. Trutat gives a double list of what he calls corres- 

 ponding plants in the Alps and Pyrenees, some of which might be 

 considered as varieties of each other. 



Altogether during our trip we noticed 106 species of RJiopalocera, 

 and we have added a few notes on the most interesting. 



Papilio Podalirius, var. Feisthamelii. — The specimens of this variety in the 

 middle of July at Vernet were rather worn, but they probably belonged to a second 

 brood, as the first brood is said to be typical, while our specimens were very black 

 and wliite. We found young larvae on some stunted blackthorns on the dry hill 

 slopes below Yernet. 



Thms rumina, var. Medesicaste. — A single specimen in fine condition was cap- 

 tured by Herr Seebold during our visit. The larvse were to be found nearly full-fed 

 at the same time on Aristolochia pistolochia, on the dry slopes below Vernet, and 

 among the rocks in the wood close to the hotel. 



Parnassius Apollo.— ■'^ot uncommon near Vernet, especially near St. Martin. 

 The specimens, though larger than the usual Swiss form, are not so fine as those we 

 took at Digne. P. Mnemosyne. — -Taken on the Col du Cheval mort at Vernet, and 

 again near the Lac de G-aube ; we did not, however, notice it in any abundance. 



Pieris Callidice. — Not uncommon in the higher regions ; on the Pla Guilhem 

 and also on the Cabaliros above Cauterets. In the latter place it was abundant, but 

 in poor condition, on July 21 st. P. Daplidice occurred, but not very commonly, at 

 Vernet. 



HucMoe euphenoides. — This beautiful little species was not uncommon at 

 Vernet, in stony places where its food-plant, Biscutella Imvigata, occurred. It must 

 be on the wing for a very long time, as we found a few nearly full-fed larvse. The 



