63 
A Gregarious Butterfly, Erebia nerine (a Reminiscence 
of the Mendelstrasse). With some Notes on the 
Lepidoptera of the Serpents of the Mendelstrasse. 
By J. W. Tutt, F.E.S. Read September oth, 1897. 
STEEP and precipitous, the rocks rise some three or four hundred 
feet perpendicularly above the Mendelstrasse, and then by steep and 
dangerous slopes continue up to the summit of the Penegal, some 
two to three thousand feet above. Hewn in the solid rock is this 
part of the Mendelstrasse, the steep rocky road that climbs the side 
of the Penegal, and leads from Bozen, at the lower end of the lovely 
Brenner valley to the Mendel Pass, which runs over the mountains 
between the Penegal and Monte Rowan into the Val di Nonne, and 
thence into Italy. 
Some two or three thousand feet below us is the broad fertile 
plain of the Adige. The large town of Kaltern lies directly below, 
and the straight lines which cover hundreds of acres of the plain 
show the vines from which the inhabitants of Bozen and Kaltern 
draw their immense wealth. 
Wild and savage enough are our immediate surroundings on this 
rock-hewn path, over which the precipitous walls hang threateningly, 
and from which every breeze dislodges stones which fall with a thud 
and rebound in a manner that augurs ill for any one they may 
strike. Here steep watercourses have cut almost perpendicular 
paths through the rocks, and their water is carefully directed into 
large tunnels which pass under the road on which we stand. A 
strong stone wall edges this dangerous path, and as we glance over 
we observe a steep slope of loose skrees, running from one to two 
thousand feet down to the edge of the wood that covers the slope 
and runs out to the edge of the valley. There is but little vegetation 
on these slopes. ‘To a nature-lover the place presents a picture of 
wild and rugged grandeur, of savage untamable magnificence, but 
life is about the last thing he would expect to find in this apparently 
hopeless and impossible spot. ‘The watercourses are brightly tinted 
with flowers, and now and then one catches a glimpse of the higher 
slopes richly clad in verdure, but there is nothing here to tempt 
insect visitors to give it a passing visit. Yet this is the home of the 
magnificent Hrebia nerine, one of the largest, handsomest, and most 
local of this Alpine genus. 
You look around. ‘The sun pours down its hot midday beams 
upon the bare rock. The road and the rocks are burning. The 
