1096 Appendix II: Phytogeography and Geology. 
the central consisting of bare elevated limestone plateaux; the southern 
a lower-lying expanse of rugged sandstone, broken only occasionally 
by ridges and basses of granite and other crystalline rocks. 
Only the following species are not known from other parts of Hgypt: 
Eruearia crassifolia. | Centaurea furfuracea. 
Fagonia thebaica. Salsola Pachoi. 
Ammodaucus leucotrichus. | Aristida Zittelii. 
Anvillea Gareini. | 
II. Arabic Desert. (D. a.)'). The neck of land which joins 
Asia to Africa, or the Ithmus of Suez (D. i.), is nearly one hundred 
miles wide; on the south side is the Gulf of Suez, on the north the 
Mediterranean. The Red-Sea and the Mediterranean appear to have 
been united in ancient days. The soil of El-Guirs is the highest 
point in this district. It is about 6 miles long, and from 20 to 
23m above the level of the sea. The soil is composed almost 
entirely of loose sand, interspersed with a few bed of hard sand 
and clay. North of Hl-Guirs the Lake Bala is situaded it is the 
principal among a series of shallow lakes, or rather swamps, through 
which the Suez-Canal passes before entering the low sandhills 
which extend frome this point to nearly Port Said. A chain of 
low sand-hills divide Lake Menzale from the smaller inland lakes. 
1'/, miles from Qantara the Canal enters Lake Menzale, and continues 
in a straight line through it for 20 miles to Port Said. The banks 
here are but slightly above the level of the Canal and the lake, 
and from the deck of a big steamer there is an unbounded view 
over a wide expanse of lake and morass, studded here and there 
with islets, and at times rendered gay and ‘brilliant with inumerable 
flocks of rosy pelicans, scarlet flamingoes and snow-white spoon- 
bills; geese, ducks, herons, and other birds abundant. From the 
mouth of the Damietta branch of the Nile to the Gulf of Pelusium 
there stretches a low belt of sand, varying in width from 200 to 
300 yds., and serving to separate the Mediterranean from the waters 
of the Lake Menzale; though often, when the lake is full and the 
waves of the Mediterranean are high, the two meet across this 
sligth boundary-line. 
Only a few species limited only to this district: Delphinium 
deserti, Delphinium Bovei, Polycarpon arabicum, Verbascum sinaiti- 
cium, Otostegia microphylla and Leucas inflata?). The proper Arabic 
or Eastern Kgyptian Desert (D. a. sept. D. a. mer.) from Wady Tumi- 
1) Barron and Hume: Topography and Geology of the Eastern Desert 
of Egypt. —- Cairo 1902. 
®) Kotschy: Die Vegetation und der Canal auf dem Istmus von Suez. — 
Wien 1858. 
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