388 | ANNUAL REPORT SMITHSONIAN INSTITUTION, 1944 
their living by exploiting the natural salt deposits situated near the 
great city-sites. 
To the east of the Yemen, and to the south of the westernmost exten- 
sion of the Empty Quarter, lies the famous region called Hadhramaut, 
a country whose size diminishes as one approaches it. To the outsider, 
the Hadhramaut comprises most of Arabia east of Aden, west of Mahra, 
and south of the desert. To the Hadhramis themselves, it includes 
only the narrow valley which bears its name, and the string of towns 
built along it. The Hadhramaut, like the Yemen, is the seat of intense 
agricultural activity, but in a much more restricted sense, since only the 
river valley and the beds of its tributaries are actually productive, 
while the nearly denuded mountain region lying between the valley 
and the sea is used for camel pasture and the passage of caravans. 
The sea coast of the Hadhramaut is a negligible geographical expres- 
sion, since the cliffs which hem in this valley to the south arise almost 
directly from the water. 
East of the Hadhramaut lies what is, to most ethnologists, probably 
the most interesting section of southern Arabia. ‘This is the half moon 
of Dhofar, a small coastal plain hemmed from behind by the Qara 
Mountains, against which the full force of the Indian monsoon unloads 
seasonal rain in abundance. Dhofar alone retains the damp tropical 
climate which, the geologists tell us, at one time characterized the 
whole southern strip of Arabia. In Dhofar survive mangrove 
swamps, miniature jungles of tropical palms, and on the slopes above 
the plain, an abundance of those small, fleshy bushes from which are 
bled the frankincense tears so greatly prized in the ancient world. 
In the highlands behind Dhofar survive pre-Arabic Semitic lan- 
guages; ? and a cattle culture comparable to that of the Toda of India 
on the one hand and of the East African Hamites and Bantu on the 
other, as well as certain customs and practices of a very primitive 
character. 
When we leave Dhofar we enter the domain of Oman proper, but 
we are no longer in the strict sense concerned with southern Arabia. 
The bulk of Oman is situated in a latitude north of Mekka, and even 
with that of Medina. Except for the alleged Negrito strain in the 
population of Cape Musandam, its relationships are primarily with 
the valley of Mesopotamia and with the coast line of Iran. Southern 
Arabia, in the strict sense of the word, cannot be said to extend 
north of the twentieth parallel. 
PREHISTORY 
There can be little doubt that, during parts of the Pleistocene period, 
southern Arabia enjoyed a much more felicitous climate than it does at 
2 Thomas, 1937b. 
