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of blue looking brilliant in the sun, whilst the P. podalirius, with 
their wings drawn up closely over the back, and the tails stretched 
out behind, just clear of the damp, were very remarkable-looking 
objects.” On another occasion, drinking from the runnels that crossed 
a pathway over an Alpine pasture on the mountains behind Bourg 
d’Oisans, I once saw P. corydon and P. astrarche in incredible 
numbers (“ Ent. Rec.,” ix, p. 80), and in my various notes on Alpine 
butterflies I have mentioned many similar facts. These lovely way- 
side pictures have been excellently described by Kane, in his pictures 
of butterfly life in Switzerland (‘“‘ Handbook to the European Lepi- 
doptera”). He says, ‘‘ The astounding profusion in which butterflies 
are met in Switzerland will readily be acknowledged by all who have 
visited the Engadine, who have seen the mountain path, when 
moistened by some overflow of pasture irrigation, paved like a lapis- 
lazuli mosaic for perhaps a yard or two with hundreds, nay, thousands 
of ‘Blues’ with expanded wings, taking a Turkish bath of moist 
vapour upon the hot damp soil, or, as some say, drinking in safety 
from the wet clay upon which they find secure footing.” 
One observation that I made, however, when in the company of 
Dr. Chapman has not yet been recorded. After a stormy night in 
the Cogne valley in August, 1894, the pathway next morning was 
covered with small puddles, and in almost every one of these large 
numbers of Czdaria populata, Larentia cesiata, and some other 
species were lying dead on the surface of the water. I could not 
surmise the cause, but it was Dr. Chapman’s opinion, I believe, that 
they had come to the water to drink, and were unable to rise from 
the surface and were drowned. 
That there may be another view of this matter J am well aware. 
Many have recorded /veris brassice and Pyramets cardui, when 
migrating, as resting on and rising again from the surface of the 
water. Sheldon reports that Euwpeclia affinitana and LE. vectisana 
rise from the water with perfect ease and fly away. Calamia 
phragmitidis floats with the greatest ease on the surface of the water, 
and Rowland-Brown noticed specimens of a Geometrid moth, 
common in the adjacent pine-woods, dipping themselves like 
swallows on the surface of the Lake of St. Moritz. Gardner records 
that whilst watching the great horse-shoe falls of the Skjalfandafljot, 
near Ljosavatn, in Iceland, he saw moth after moth fly deliberately 
into the falling water and disappear, the gleaming falls seeming as 
attractive as artificial light. Piepers relates that whilst he stood on 
the bank of the river just above the beautiful waterfall of Maros, in 
South-west Celebes, he saw a specimen of Papilio helenus come flying 
over the water, when suddenly it half closed its wings and dived 
down, so that the whole body and about a third of the wings, which 
slanted upwards, were immersed. It then raised itself again out of 
the water and flew away. Are we to suppose that these instances 
really do show that certain Lepidoptera voluntarily bathe, and that 
the internal bath of some species is as needful as the external bath of 
