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PLANTS OF THE SUDAN 

 COLLECTED BY DR. D. T. MACDOUGAL. 



By A. B. Rendle, D.Sc, F.R.S. 



Dr. MacDougal's work on desert vegetation, and as Director 

 of the Desert Laboratory at Tucson, Arizona, is well known. He 

 has recently made a trip to the dry regions of the Sudan and the 

 Egyptian Desert, the results of which will shortly be published. 

 The plants collected on the expedition by Mr. Sykes and himself 

 have been determined by members of the Staff of the Department 

 of Botany of the British Museum, and will in due course be de- 

 posited in the National Herbarium. As a certain proportion of the 

 species have not been recorded for the area in question, it has been 

 thought worth while to publish a systematic list. The collection 

 contained one new species, a Composite, which Mr. Spencer Moore 

 has described as Geigeria Macdougalii. 



According to information furnished by Dr. MacDougal the 

 expedition was undertaken for the purpose of studying the physical 

 and biological conditions of the eastern and western slopes of the 

 mountain range between the Nile and the Red Sea, and of an 

 expanse of the Libyan desert. 



The party landed at Port Sudan, Jan. 20th, 1912, and after a 

 few excursions across the lower slopes and into the foothills as 

 far as Sal Lorn, a saloon car was chartered from the Sudan 

 Government Railway, in which they travelled across the mountains 

 to Atbara and Khartoum. The principal collection on the eastern 

 side of the range was made at Kamobsana, where the bed and 

 margin of Khor Adit and a mountain to the eastward of the rail- 

 way station rising to a height of 2700 ft. were examined. The 

 crests of the range attain a height of over 5000 ft. in this region, 

 but the railway route passes through at much lower elevations at 

 Sinkat, Erheib, and Gebeit. 



Some time was spent at Talgwareb on Khor el Ushari, on the 

 long gentle western slopes leading down toward the Nile, at which 

 place the conditions are much more arid than on the eastward 

 exposures. Nearly one hundred and seventy species were noted 

 in the ten days' work in this region. 



From Khartoum the party came down the Nile by rail and 

 steamer to Luxor, where the train was taken to the oasis of 

 Kharga. Here a caravan was organized, and, starting on Feb. 

 11th, a journey of nearly six hundred miles was taken into the 

 Libyan desert. The old caravan track was followed from Nadura 

 in the oasis of Kharga to Tenida, in the oasis of Dahkla, and then 

 to Smint, Mut, Rashida, and Qasr Dakhl. The ascent of the 

 escarpment was made from the last-named place, and the sand- 

 lanes through the great dunes were followed in a direction slightly 

 west of north to the oasis of Farafra. The route now ran to the 

 north-eastward to the oasis of Baharia, which, like all of the 

 oases, lies at the bottom of a great depression. Ascending the 

 escarpment on the eastern border of the basin late in February 

 Journal of Botany. — Vol. 51. [Sept. 1913.] x 



