2 FOREST FLORA OF JAPAN. 



Diospyros Kaki, and probably Diospyros Lotus, Chionanthus retusa, Paulownia imperialis, 

 Catalpa ovata, Lindera strychnifolia, Ulmus parvifolia, Thuja orientalis, Ginkgo biloba, Podo- 

 carpus Nageia, Podocarpus macrophylla, and Pinus Koraiensis. If these species/ twenty-nine 

 in number, are deducted from Professor Gray's enumeration, there will remain 139 species in 

 fifty-three genera, or a smaller number of both genera and species than he credited to eastern 

 America. This, however, does not alter the fact that the Japanese region for its area is unsur- 

 passed in the number of trees which inhabit its forests. 



Indeed, the superiority of the forests of Japan in the number of their arborescent species 

 over those of every other temperate region, eastern North America included, in proportion to 

 their area, lias certainly never been fully stated, as perhaps I shall be able to show, having 

 made two years ago a somewhat extended journey through the northern and central islands, 

 undertaken for the purpose of studying Japanese trees in their relations to those of North 

 America. The case, perhaps, can best be stated by following Professor Gray's method, and 

 making a new census of the inhabitants of the Japan-Manchurian forests and of those of 

 eastern America, as these two regions extend through nearly the same degrees of latitude, and 

 possess somewhat similar climates, although Japan has the advantage of a more equally 

 distributed rainfall and a more equable climate, and offers a far more broken surface it4;han 

 eastern America, with mountains twice the height of any of the Appalachian peaks. 



As the true Atlantic forest extends west to the eastern rim of the mid-continental plateau, 

 the American region, for purposes of proper comparison, may be extended to the western 

 limit of the Atlantic tree-growth, although this will add to the American side of the account 

 a few genera and species of Texas, like Koeberlinia, Ungnadia, Parkinsonia, Prosopis, Acacia, 

 Chilopsis, and Pithecolobium, which Professor Gray did not include in the enumeration from 

 which his deductions were made. The south Florida species are again omitted, and those 

 plants which grow up with a single stem will be considered trees. In eastern North America, 

 that is in the whole region north of Mexico and east of the treeless plateau of the centre of 

 the continent, but exclusive of south Florida, 225 species of trees, divided among 134 genera, 

 are now known. The Japan-Manchurian region includes eastern Manchuria, the Kurile 

 Islands, Saghalin, and the four great Japanese islands, but for our purpose does not include 

 xj the Loochoo group, which, although it forms a part of the Japanese empire politically, is 

 tropical and subtropical in the character of its vegetation, which, moreover, is still imperfectly 

 understood. In this narrow eastern border of Asia there are now known 241 trees divided 

 among ninety-nine genera. The extra Japanese portion of the region contributes but little 

 to the enumeration. In Saghalin, Fr. Schmidt ^ found only three trees which do not inhabit 

 Yezo, and in Manchuria, according to Maximowicz ^ and Schmidt,* there are only eighteen 



1 A number of shrubs, familiar in western gardens, and kerrioides, Cercis Chineusis, Enkianthus Japonicus, Forsy- 



usually supposed to be Japanese from the fact that they were thia suspensa, Olea fragrans, Tecoina grandiflora, Daphne 



first known to Europeans in Japan, or were first sent from Genkwa, Edgeworthia papyrifera, and Wikstrcemia Japonica. 



that country, are also Chinese or Corean, and in Japan are Nandina domestica, the most universally cultivated orna- 



only found in gardens or in the neighborhood of habitations. mental plant in Japan, is probably not a Japanese plant. 



Among them are Clematis patens, Magnolia stellata, Mag- although Kein states that it grows wild in Shikoku. 



nolia obovata, Berberis Japonica, Citrus Japonica, Prunus ^ Reisen in Amurland. 



tomentosa, Prunus Japonica, Spirsea Thunbergii, Rhodotypos ^ Prim. Fl. Amur. * Reisen in A murland. 



