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The Species of the Genus Larix. 
1906, p. 309. — ELwes & HEXRY: Trees. Gr. Brit. and Irel. II, 1907, 
p. 346. — DALLIMORE & JACKSON: Handb. Conif. 1923, p. 298. — 
L. dahurica var. Principis Rupprechtii, (Mayr) REHDER & WirL- 
son, 1914, in SARGENT: PI. Wırson II, p.21 (p.p.). — REHDER, in 
Journ. Arnold Arb. IV, 1923, p. 121. — REHDER: Man. Trees and 
Shrubs, 1927, p. 52. — Hsen-Hsu Hu & Woon-YounG CHUN: Icon. 
Plant. Sinicarum, 1927, Pl. 1. 
Inhabiting an area which is now completely separated 
from that of L. Gmelini and var. olgensis, another variety 
of L. Gmelini is found, namely, var. Principis Rupprechtii. 
Its area of distribution extends over the mountains west 
and north of Peking through the provinces of Shensi and 
Chili. No forest is found north of the Yellow Sea. (Maps 
IV og V). 
The province of Shonking, north of the Yellow Sea, 
was once rich in forests, which in earlier times probably 
formed the link between the two now widely separated forest 
tracts, containing respectively L. Gmelini var. olgensis and 
var. Principis Rupprechtü. The separation has taken place 
partly in recent times, and has been caused by extensive 
afforestation, which in that district has produced a wide 
extent of country devoid of forest (W. PATSCHKE in Engl. 
Bot. Jahrb. XLVIII, 1913, p. 705). 
In 1903, HEINRICH Mayr discovered in Wutaishan, one 
of the most southerly localities in its area of distribution, 
the material on the basis of which he put forward the 
species L. Principis Rupprechtü. Mayr’s cones (Fig. 94 in 
Fremdl. Wald- und Parkb.) are very large, and present 
many points of difference from those of L. Gmelini. The 
larch which Wma. Purpom found in 1909 in the same 
district — near some temples in the village of Wutai — 
has rather smaller, or much smaller, cones (Arnold Arbor- 
etum Expedition to the north-west of China, 1909, No. 
