ic 4 Wy iiaiy? = aeiaee 
Explorations in the Amoor Region. 405 
 eclivities of the Adoncholon mountains, of which the summits 
alone are overgrown with stunted birch-trees (these are often, 
however, found in great density along the entire northern slope 
of that chain), are referable to the same region.* ‘To the eastward, 
however, almost on the meridian of T'sagan-olu (116° 43’), two 
rows of woody elevations extend from east to north, intersecting 
each other at the most westerly lower range of the Buko-Ha 
_ where the eastern branch terminates. The bare elevations run- 
ning from this knot to the south expand the farther they extend, 
and form, near the frontier, the wooded table-land of Altangan, 
80 called after one of its principal valleys. 
e abovementioned mountains, which terminate in Buko- 
Hada, form’first on their eastern, then on their northeastern ex- 
tension, a water-shed between the affluents of the Onon and 
rgun; t azimur river takes its rise on its northern side. 
The Altangan table-land lies between two systems of saline 
; 
, 
ae The region, however, between the Urulungui Argun, 
- Altangan plateau loses its vegetation more and more towards 
€ south; on the frontier at Abagaitu it is intersected by parallel 
northern, which longer preserve the moisture of the soil, and so assist vegetation ; 
The most every plant withers in summer 
the goon’ cause is attributable to the circumstance that the 
Re ogy spring become soon: b an ee the 
Posite, oo snow leaves the ground earlier (being, in. - Lge A th y Pus 
limit ebruary), thus offerin, t spreading “idles, » 
ats of wood and bush vhantasiais are not governed in these agp get the 
Paid Sud - Winter, but solely by the dryness of the soil and sultriness of the sum- 
, t The Uralungui valley probably commences in the vicinity of the Chinese 
by to the west of the Altangan plateau. 
