are 
exlvii 
if he strikes the right spot at the right time, will be of a different 
opinion. For him it is a land of riches, where he sees more 
treasures run and fly about than he can gather in. From 
mid-April to late in June when the low vegetation is at its 
best, the number of individual insects one sees in favourable 
localities is astounding. Unfortunately one cannot depend on 
finding these riches every year. When for a year or two an 
insufficient rainfall or entire absence of rainfall occurs, as it 
occasionally does, or when one arrives after the vegetation 
has been decimated by locusts, insect life is poor. Before 
going to the High Plateaux or the Desert for the purpose of 
collecting Lepidoptera, it is advisable to inform oneself before- 
hand about the meteorological conditions which have prevailed 
the winter and autumn before. In 1920, for instance, there 
was hardly any wild vegetation on the hills near Biskra and El 
Kantara and Lepidoptera were scarce, and in 1919 collecting 
was very poor around Batna. Our collecting tours on the 
High Plateaux have generally been successful; only when 
visiting Tebessa near the Tunisian frontier we struck cold and 
misty weather and had to leave after waiting a few days in 
vain for sunshine. Khenchela, likewise on the eastern plateau, 
at the foot of the Aurés, is a very good spot accessible by rail. 
The Hotel de France is quite good enough for a collector, and 
the town has the great advantage of being on the collecting 
ground, which is good and varied. On the one side there are 
the wooded Aurés Mountains with the hot springs and rich 
vegetation of the Fontaine Chaude about 5 km. to the west of 
the town, while east, south and north the country is open and 
has a rich steppe fauna. Timgad, the most imposing of the 
Roman ruins of North Africa, cannot be recommended as a 
collecting ground; the surroundings are too uniform, too open 
and wind-swept. Lambessa and Batna, on the other hand, 
offer a greater variety of localities with a prospect for the 
collector of obtaining the special treasures of the Aures 
Mountains in addition to the insects of the open plains, The 
best spot in which we have collected was Guelt-es-Stel on the 
line from Alger to Laghouat, about halfway between the 
northern and southern Atlas. Guelt-es-Stel is not a village, 
but a wayside bord] or caravanserai, where the kind and efficient 
