NORTH-WEST MONGOLIA AND CHINESE DZUNGARIA. 389 
Primula and Trollius appeared as soon as the snow had gone, but in July the 
‘shady forest association began to creep in and apparently constituted a large 
portion of the vegetation during the autumn. 
On the Upper Shabash River forests of Pinus sibirica with a variety of 
Alnus Alnobetula grew in dense jungles on the shady sides of the valley. 
‘On the valley sides facing the sun, however, the mountain slopes were covered 
prineipally with serub of Birch, Aspen, and Poplar, accompanied by a vigorous 
flora of Euphorbia lutescens, Pronia anomala, and Aconitum. septentrionale. 
Relics of old forests of Pinus sibirica and Abies sibirica were to be seen in 
places. Large logs of these trees littered the mountain-sides up to 4000 feet, 
and there was considerable evidence that the Pine forest had been replaced 
by a broad-leaved forest within comparatively recent times, 
On the Ulug Tag mountain, an isolated peak between the watershed of the 
Shabash and Japsa Rivers, I observed the following floral zones typical of 
the Sayansk system, beginning from the valley bottom upwards. 
Zone 1. In the valley bottoms at 3000 feet Larch-forest association pre- 
dominated, containing Potentilla fruticosa, Betula nana, Larix sibirica, and 
Erythronium Dens-canis. Erythronium Dens-canis is of considerable interest, 
since its roots and tubers are used during the summer as food by the nomad 
tribes of Urian Hai or Soiots, who wander with reindeer all over these forests. 
The root is dried in the sun, and eaten with reindeer’s milk. 
Zone 2, at 4000 feet, consisted of thick forests of Pinus sibirica and Picea 
-obovata accompanied by Vaccinium Vitis-Idea and Sphagnum. 
Zone 3 began at a height of 4500 feet and consisted of Pinus sibirica and 
Abies sibirica in а creeping form. 
Zone 4, between 4500 and 5500 feet, consisted of serub-like Pinus sibirica 
and a widespread distribution of Rhododendron chrysanthum, 
Zone 5, from 5500 to 8000 feet (the mountain summit), containing only 
Betula nana in a creeping and very stunted form. 
Descending the Shabash River from its source, we traversed for a day 
forests of Pinus sibirica with its attending flora. Halfway between its source 
and its junction with the Bei Kem River, Larch forest with its floral 
association began. In this typical forest of Larix sibirica the trees grew 
from 10 to 12 feet apart, running from 3 to 6 feet in girth, and averaging 
about 75 feet in height. The ground flora here was typical of the Larch- 
forest association throughout the Upper Yenisei plateau and consisted of 
Spirea, Luphorbia lutescens, Polygonum polymorphum, Dracocephalum 
Ruyschiana, Veronica longifolia, Bupleurum longifolium var. aureum, Poten- 
tilla nivea, Myosotis palustris, Achillea impatiens, Aster alpinus, Galium 
boreale, Valeriana sambucifolia, Trifolium Lupinaster, Sanguisorba officinale, 
Oxytropis sp., Poa altaica, Phyllodoce taxifolia, Rosa acicularis, Vaccinium 
uliginosum, Lonicera cærulea, Pedicularis uncinata, Aconitum septentrionale. 
A few areas of Pinus sylvestris were to be seen growing on sandy banks by 
LINN. JOURN.— BOTANY, VOL. XLI. 2G 
