- 
elx 
to the Coleopterist who grubs about in the sand near tufts of 
plants, the snake springing forward when disturbed. It lies 
in the sand waiting for a small bird or mammal to approach 
within reach of its poison fangs. 
The number of moths not yet found outside the Algerian 
Sahara is not inconsiderable, but there are no butterflies which 
as species are restricted to the desert, the butterflies all 
being immigrants from the north as regards the northern 
districts of the desert and from the south in the southern 
districts. Danais chrysippus, the common Ethiopian species, 
occurs as far north as the southern Oued Mya, but reaches 
neither Tougourt nor Ghardaia. In the same southern district 
occurs Pieris glauconome, a species of the Nile countries 
extending to East Africa, Arabia, Persia and further east. 
Among the butterflies of northern origin which have developed 
into special desert forms the most conspicuous are Papilio 
machaon, Euchloé fallowi and Melitaea didyma. The larva 
of P. machaon from the desert resembles the larva of P. 
hospiton; it would be most interesting to breed in Europe 
two or three generations from chrysalides gathered at Bou- 
Saada or further south and find out whether the caterpillar 
would throw back to the ordinary European form. The 
moths special to the Sahara are much more numerous; we 
mention Liparis oberthurt Lucas, Casama uniformis Roths., 
Chilena hilgerti Roths., Ch. geyri Roths., Phryganopsis uni- 
puncta Hamps., Nygmia charmetanti (Mab. & Vuill.), Athetis 
oberthurt Roths., Buxoa hoggari Roths., Hadula pulverata 
(Bang-H.), H. griseola (Roths.), Crypta rosacea Rebel, C. 
leucoptera Hamps., Anydrophila sabourodi (Lucas), Anumeta 
sabulosa Roths., A. major Roths., A. straminea (Bang-H.). 
The beetles most commonly observed in the desert are the 
Tenebrionidae and some Coprophagidae, besides species of 
Cicindela, Graphipterus, Anthia and in the Chott district 
Scarites and Megacephala. The Megacephala typifies a distri- 
bution common to many species and genera of animals, this 
large Cicindelid, of nocturnal habits, reaching into Spain and 
going eastward as far as Mesopotamia. In the oases of the 
desert a Longicorn beetle, Polyarthron pectinicornis, is found in 
the root-stocks of the date-palm; it evidently does not occur 
in the northern oases of E] Kantara and Biskra, but is known to 
