HAMMAM E’lHEA 
173 
line being apparently determined by obstacles encountered. There 
were about ten caterpillars to the foot, so that the column covered 
twelve feet of ground. Three times I moved the leader from the 
van to the rear, but this seemed to make no difference, the column 
went on unperturbed. If a larva were taken out of the middle the 
ranks very soon closed up. Larvae taken from the ranks and placed 
near the tail of the column failed to find it, unless placed very close 
to it. They travelled with the head of one touching the tail of the 
next ahead, and they appear to march along a thread of silk. Pre¬ 
sumably this thread is laid down by the leader, but I failed to assure 
myself of this. 
Next to the Lepidoptera in importance, so far as my collection 
was concerned, stood the Hymenoptera. To begin with the humble 
but industrious ants: of these five species occurred— Aphaenog aster 
testaceo-pilosa, Lucas, of which a colony was found under a stone in 
the fir-wood; they were remarkably shy of light; and A. barbara, big 
black fellows which were also very shy, and in that respect contrasted 
with the small yellow Tetramorium caespitum , Linn., which had a 
colony under the same stone. At the summit of Mont Samsam 
(2800 ft.) I found under stones communities of Monomorium salomonis, 
Linn., and Camponotus cruentatus, Latr., the last-named being remark¬ 
ably sluggish in its movements. 
The only Scoliid was Dielis ciliata , Fabr., which was very abundant 
in two spots, a bank between the hotels, and a vineyard south of the 
hotel, towards Yesoul, at an altitude of about 1600 ft. This insect has 
tough integuments; it flies close to the ground among the Calendula 
algeriensis, Bois. Beut., and C. arvensis, Linn. The bright orange- 
blossoms of these small Marigolds are quite a feature of Algeria—till 
the evil season when the vineyards are hoed. D. ciliata was also 
taken at the yellow flowers of the wild Jasminum fruticans , Linn. 
It is curious that I came across no Pompilus nor Eumenes at Hammam 
E’ihra, but of Odynerus I got two: 0. ( Hoplopus ) consobrinus and one 
0. ( Ancestrocerus ) parietum , the last at Hawthorn blossom. The true 
Wasps were two Polistes gallicus and a female Vespa germanica , Fabr., 
the latter found in the forest. Of Halictus I took several:— II. ochr~ 
aceo-vittatus, Hours., one; H. (?) malachurus, two females; Halictus 
sp., one; II. (? )costulatus , Kriech, one (though Mr. Saunders thought 
this might possibly be new); also Halictus near to villosulus , Smith, 
one. Naturally enough there were several species of Andrena; of 
A. minutula, Kirby, which thoroughly deserves its name, I got seven; 
of A. sardoa, Lepel., one; of Andrena sp., one; of A. Jlavipes, Panz., 
as many as thirteen, of these one was taken by Miss M. J. Donald on 
