FAUNA AND FLORA OF SINAI, PETRA, AND WADY 'ARABAH. 35 



Cotyledon umbilicus (?), Linn.; Linaria macilenta, Dene.; Verbascum 

 sinuatum, Linn.; Phiomis aurea., Dene., and Boerhavea verticillata, Pair. 



Many desert species of Reaumuria, Ochradenus, Zygophyllum, Morettia, 

 Zilla, Acacia, Retama, Ruta, Ifloga, Lycium, Trichodesma, Forgkahlea, 

 Asphodelus, Anabasis, Ephedra, and grasses already mentioned, occur also 

 in Wady Hartan, the name which the Bedawin invariably give this wady. 



It will thus be seen that there is no appreciable break as yet in the 

 continuity of the Sinaitic flora as we travel up the Widy 'Arabah, but an 

 increase of species from eastwards and northwards. 



The Widy Harlin is at first wide and arid, but after a few miles 

 vegetation rapidly increases with moister conditions. The flanks of the 

 Edomitic limestone plateau are better supplied with moisture than the 

 Sinaitic granite. Banks by the edge of this valley at a moderate elevation, 

 1,000 to 1,500 feet above sea-level, had a sparse coating of mosses and 

 other cryptogams. The mosses were chiefly of the Tortula genus, of 

 which five species were collected. Side by side with these grow the 

 desert species above mentioned in great luxuriance. Demia cordata, for 

 instance, climbed to a height of 10 or 12 feet in retem bushes; the 

 support being as well developed as the climbing plant. In the open 

 desert, Dcemia, as mentioned by Mr. Redhead, lies sprawling on the 

 ground, its several stems sometimes closely twisted into a thong towards 

 their extremity, so that all circulation is stopped, and the young shoots 

 are strangled. This is probably due to changed conditions having de- 

 prived it of its normal support, which it rarely finds in the desert, and 

 even seems there to have lost the power of utilizing. For I have seen it 

 strangling itself side by side with bushes of the very sort which here gave 

 it so much assistance. The desert plant was more plentifully milky, and 

 we have here seen at work agencies which are giving rise to a modified 

 form, in better harmony with its environment. 



From the summit of Jebel Abu Kosheibeh, which I climbed with 

 Dr. Hull, an unusual sight was observed : a stream, small in size, but con- 

 taining a good body of water, rushing down the cliffs about half a mile to 

 the south-eastward. I could distinguish with my spy-glass the growth of 

 arundos and oleanders that fringed its banks, but unfortunately there was 

 no time to examine it more closely. Running water was once seen before 

 on Jebel M^lsa. 



5—2 



