I.— HISTORY OF THE BOTANICAL EXPLORATION 
OF ADEN. 
Arabia is the least known country of Western Asia. Colonel Wahab 
who was engaged for some years in the delimitation of the boundary to 
the north of Aden has occupied himself with a very close examination of 
the possibilities that may occur for further exploration in that vast 
peninsula. His observations, though made with a view to geographical 
and archaeological research, are equally applicable to the botanical 
exploration of the country. He says 
“ Throughout Northern Arabia, that is, north of a line from Jidda, 
passing through Taif and across Nijd to Hofuf and the gulf, the peninsula 
has been crossed and re-crossed at intervals sufficiently close to enable us 
to form a fair idea of its general character. South of this line no trade 
or pilgrim route crosses it ; few Europeans have penetrated more than 
100 miles in a direct line from the coast, and these have found their way 
barred by the sands of the Dahna. On the east and south coasts the 
strip between this desert and the sea has been explored first by the Indian 
Marine surveys and more recently by Zwemer in Oman and by Hirsch 
and Bent in Hadramaut ; on the west, Glaser and HaHvv, both skilled 
archaeologists, reached the western edge of the desert and explored the 
seats of ancient Sabaean and Minaean civilization in Marib and Nejran. 
Omitting the half-million square miles of the Dahna desert as unprofi- 
table waste, there still remain the northern districts of Yemen, the whole 
of the Asir highlands, and the hinterland extending north-east to the 
borders of Al Hasa as a field for the geographical explorer. A route 
from Sana northwards to Taif would lead through one of the most 
interesting districts of Arabia, of which nothing is known at first hand, 
except from the meagre accounts given by Tamisier and other French 
officers of Mehemet Air’s army between 1830 and 40. 
t( The difficulties and risks of such a journey are serious, The whole 
Bed Sea coast is Turkish, and British subjects have not, of late years, 
found travelling in Turkish possessions a safe or easy matter. The 
independent tribes in the interior of Arabia and northern Yemen are 
somewhat fanatical followers of the Iman, whose capital Sada lies in 
the direct road north from Sana. The British authorities would forbid 
any one entering from the Aden district. The only approach to this 
hinterland would therefore seem to be from the coa^t some distance te 
