66 Nr. 2. C. H. OSTENFELD and C. SyRACH LARSEN: 
1,5 m. A warm, fresh soil is especially favourable to its 
srowth, and in such localities it forms more or less pure 
groups, while it is otherwise met with in forests scattered 
among Pinus silvestris, Picea obovata, Abies sibirica, and 
Pinus cembra var. sibirica. 
On the forest steppes the larch is the dominating tree. 
On the steppe between the Sajan Mountains and Tannu-ola, 
small sporadic specimens of the larch are found along the 
upper course of the River Jenisej. West of the Sajan 
Mountains, on the Abakan steppes, it is found where the 
ground rises in low ridges, and it also occurs along the 
courses of the rivers and on the small islands lying in 
their beds. Here it is often mingled with Pinus silvestris, 
birch (B. pendula), and poplar (P. laurifola, P. tremula, and 
P. nigra) (PRINTZ, 1921, p. 112). Good illustrations of L. 
sibirica are to be found in Printz’s book, and in B. A. 
KELLER’s paper: Im Berg und Tal des Altai I, 1914, Plate 5 
(see Fig. 20). 
Of the other species of larch, L. sibirica most re- 
sembles L. decidua, of which it has sometimes been regarded 
as a variety (Loupon, REGEL, and KORSHINSKY). 
In the absence of flowers or cones, they are also diffi- 
cult to distinguish; their leaves are similar, although those 
of L. sibirica are somewhat longer than those of the latter; 
the light-coloured bark is another point of resemblance. 
Under cultivation, the young tree of L. sibirica is 
characterised by its crown, which is remarkably narrow, 
but the young tree is perhaps most easily recognised by 
the sweet, pleasant scent which becomes apparent under 
dry conditions, and which is not found in the European 
larch. 
The cone of L. sibirica is, when flowering, green, or 
