BOGHARI TO LAGHOUAT. 21 



eaten. In fact, at Boghari the effects of grazing were first noticed, though 

 afterwards repeatedly seen. Only such plants as are poisonous, distasteful, 

 or heavily armed survive the predatory attacks of the countless numbers 

 of domestic animals. 



The habitat of Pinns halepensis, which thus extends to the very edge of 

 the steppes, is to the east and west of the town. To the west it forms an 

 open forest and is associated with Qiiercus ballota, growing on the crest and 

 on the northern slopes of the low mountains. Its abundant fruit, together 

 with acorns, is gathered assiduously by the Arabs for food. Jttniperus 

 oxycedrus and /. phcenicea also occur. 



After leaving Boghari and the plain by the Oued Chelif, the route goes 

 among low, rounded hills for a distance of about 24 kilometers, when it 

 strikes boldly across the wide-extending plain. The general appearance of 

 the vegetation, away from the intensely salty chotts, is that of low-growing 

 shrubs on the plain, and of somewhat higher shrubs or low trees along oueds. 

 Of the former, perhaps the most abundant are NocBa spinosissima and 

 Haloxylon sp., and by the oueds Tamarix sp. and Zizyphus sp. Near Ain 

 Oussera is a wide belt of Stipa tenacissima, the alfa grass, which occurs 

 nearly to the exclusion of other species, and a second belt of alfa, several 

 kilometers in width where crossed, was seen very soon after leaving Guelt- 

 es-Stel. At each of these places were seen large piles of the grass baled 

 ready for hauling to Algiers. 



The alfa, or bunch-grass, covers large areas in Algeria as also in Spain. 

 In November the long leaves of the grass are dry, tightly rolled, and rush- 

 formed, in place of being flat as during the rainy season or period of growth. 

 The species reproduces largely by means of much-branched rhizomes, from 

 which spring the young, fleshy leaves, enlarged at the base. In Algeria, 

 "situees en territoire civil," there are 543,620 acres of alfa, mostly on the 

 High Plateau, but a part along the littoral in the province of Oran, west 

 of Algiers. The leading environmental influence upon the peculiar dis- 

 tribution of the species is apparently that of rainfall, reacting in this respect 

 very like plants with storage organs, avoiding alike regions where the rain- 

 fall is excessively heavy or where it is so little as to cause marked desertic 

 conditions. It is apparently confined to sandy soils and is replaced by 

 others wherever the soil of a region (otherwise appropriate for its growth) 

 is of clay or is charged with any considerable amounts of salts. It is an 

 important article of export from Algeria. Its total tonnage is said to 

 amount to 80,000 each year, bringing appro.ximatel}^ $1,500,000. It is 

 sent to England, Belgium, and France, and used in the manufacture of 

 fine grades of paper, light, strong, and of a silky texture; also in making 

 baskets, hats, and mats, for which a superior grade of the grass, command- 

 ing especially high prices, is employed (Kearney and Means, loc. cit.). 



Among other species commonly seen in crossing the steppes are various 

 salt-bushes, such as Haloxylon articulaUim and Anabasis articulata and 



