146 AN ANALYSIS OF THE FLORA OF SINAL 



If we omit from consideration the ubiquitous species (74) classed in 

 the last column, there will be found to be a very small proportion of 

 species common to Sinai and Europe, almost all of which belong, of 

 course, to the group classed as essentially Mediterranean. In round 

 numbers, the Sinaitic flora is almost exactly 500, of which less than a 

 third is common to Europe. Of this 1 50 species or thereabouts, at least 

 twenty have almost certainly been introduced by human agency from 

 Europe to Sinai, and a large proportion of the remainder are so wide- 

 spread as to afford now but slight clue to their original ' centre of disper- 

 sion.' We must, therefore, seek some other flora to help us to study that 

 of Sinai. 



If the European flora was found to form any considerable portion of 

 that of Sinai, it would be probably in the Plateaux region, which is, how- 

 ever, conspicuously non-European, as will be presently seen. 



DESERT FLORA. 



If we consider the first column of Desert species, we shall find eight 

 peculiar to Sinai, of which several belong to a slightly more elevated 

 region than that which they must inhabit before they can extend their 

 range in existing circumstances across the low-lying desert strips which 

 isolate Sinai from neighbouring countries. They hardly, however, pertain 

 to the Plateaux region. Of the remainder, twenty-six do not reach 

 Egypt, but are confined to Sinai and the immediately adjacent parts of 

 Palestine and Arabia Petraea, as Edom, Judaea, Midian or Mount Seir. 

 These may have originated in Sinai, and as yet, since its union to Africa, 

 spread no further west. I incline to think these are often of modern 

 development, due to a climate which has only arrived at its present 

 peculiarities since the glacial epoch. The rest of this column, about forty- 

 five in number, are species extending westwards to Egypt, but otherwise 

 localized either in Sinai only or as above, with the exception of a very few 

 occurring also in the Syrian Desert. Viewed in the above light of recent 

 development, and more especially in connection with the many forms to 

 which some genera, as Fagonia, Tamarix, Reseda, Reaumuria, Astragalus, 

 Zollikoferia, Salsolaceae, Andropogon, and others, arc (to the confusion of 



