42 
H. Takeda. 
cold is, however, much greater than in Britain ; e.g., in Tokyo the 
mean temperature of the year is 13-8'C, the maximum being 36-6 
and the minimum 
Ill.—C omparison and Origin of the Flora. 
Under such geographical, geological, and climatic conditions 
one expects to find a well-developed, varied, and abundant flora. 
This expectation will be realised, for the traveller meets with 
beautiful vegetation and an endless variety of plants throughout 
the country. Up to 1904 some 4,400 species of Cryptogams were 
recorded, and in the Index of Japanese Plants which has just been 
completed some 6,000 species of Phanerogams are enumerated, 2 we 
know, therefore, that there are not less than 10,000 species of plants 
indigenous to Japan. This number, however, does not include the 
plants of Saghalien and Corea, which came into the possession of 
Japan after the above-mentioned index was commenced. 3 An 
exhaustive survey of plant-species is not yet possible, for new 
species and varieties are constantly being published. 
The flora of Japan belongs to Drude’s Eastern Asiatic Region. 
Although the Empire is surrounded by seas, in the west it is closely 
connected with Manchuria through Corea, in the north it reaches 
Kamtschatca by the Kurile Islands, and Alaska through the 
Aleutian Islands, and also has a connexion with Amurland through 
Saghalien. On the other hand the Loochoos and Formosa join it 
to Southern China, the Philippines and the East Indian Islands. 
Thus, except on the eastern side, it is closely connected with other 
countries, and their respective floras show many signs of a close 
relationship with that of Japan. 
It is rather difficult to say exactly when the archipelago of 
Japan separated from the Asiatic Continent, but there is evidence 
that Japan was connected with the mainland of Asia until a com¬ 
paratively recent period. Plants indigenous in the eastern parts 
of Asia are also found in Japan. Teeth and various hones of the 
mammoth have also been discovered in several parts of the country. 
1 An example of the mean temperature in Tokyo is as follows (in C.) :— 
Jan. Feb. March April May June July 
2-8 3-6 6-8 12-4 16 6 204 24-2 
Aug. Sept. Oct. Nov. Dec. Year 
256 22-2 158 10-1 5-1 138 
2 Matsumura, Index PI. Japonicarum, 1904—1912. The last volume of 
this Index includes but a few plants published after 1910. 
* There are known more than 300 species of higher plants from the 
Japanese part of Saghalien, while in Corea there are roughly 2,150 species, 
of which about 200 are endemic. (The latter information was kindly supplied 
by Dr. T. Nakai, the author of Flora Koreana). 
