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from the Atlantic on the west to Tunis on the east, is called by various 

 names in various districts, and is divided into many distinct groups. 

 But the mountain wall will everywhere be found between the Medi- 

 terranean and the Sahara, sometimes expanding into a broad table 

 land, 3000 feet in height and from 20 to 30 miles in width, and some- 

 times, as in the province of Oran, narrowed into ridges, whose higher 

 summits command alike the Sahara and the Mediterranean. 



As far as I could make out this great range divides the whole of 

 Algeria into two distinct zones of climate, in which the flowers and 

 insects differ greatly. The northern slopes, whose waters fall into the 

 Mediterranean, get a good deal of rain and much fog. The vegetation 

 is most luxuriant, much resembling that of Southern Spain or Italy, 

 and the butterflies are much what might be met with along the shores 

 of the Western Mediterranean. The southern side of the watershed, 

 whose rivers flow into the Sahara, presents a very different appearance. 

 Bare and rocky ridges rise from sandy or stony levels ; near the 

 streams and in the lower valleys are lovely oases of palm trees and 

 fruit orchards and corn fields, but the intervening country is mainly 

 clothed with prickly shrubs, if indeed it can boast of any vegetation 

 at all. Yet amid the stones and sand bloom flowers quite unlike those 

 of the European flora, and on these rocky ridges, unpromising as they 

 look, Teracolus Nouna, JEuchloe Pechi, and E. Fallout are to be found. 



Between the Tell and the Desert, north-east of Biskra, rise the 

 Aures, the highest mountain group in Algeria ; several of their 

 summits attain a height of 7500 feet and upwards, and these are 

 white with snow as late as mid April. All the Aures valleys possess 

 beautiful snow-fed streams flowing southwards to the thirsty sand, 

 which presently swallows them up. Of the insects of this district 

 little or nothing is known, and I greatly regret that I can add nothing 

 to our knowledge, for although I spent fourteen sunny days of March 

 in exploring the main valleys, it was then too early, even for the 

 flowers. 



The warmer portions of Algiers are, however, the best butterfly 

 quarters that I have ever visited in February. Miss Gilbertson and 

 I landed at Algiers on February 6th, and stayed there three days. 

 We joined Miss Fountaine, and made excursions to several promising 

 fields and copses behind Mustapha Superieur, taking a good many 

 common Mediterranean insects, and one or two fresh specimens of 

 Thestor mauritanicus. G. Cleopatra was abundant, and L. argiolus 

 already on the wing. Then we went to Constantine, where there is 

 very good collecting ground close to the north-east side of the town. 



