

low.] ON THE DISTRIBUTION OF THE FORMOSAN CONIFERS. 57 



though, I need scarcely say, not with geometrical strictness. And it is 

 clearly seen that North China has the characteristics of both the Border 



and Central Florules a fact which one would do well to bear in 



mind in studying the origin of the two florule. 



I will not here discuss as to where the inhabitants come from, nor 

 will I dwell upon the question whether or not we grant the theory of 

 the centre of creation. For in this way we find no difficulty in acknow- 

 ledging the natural economy, the manifestation of which is indispensable 

 in concluding that North China is the origin of the florules. 



Thus I am inclined to think that the two florule originated in North 

 China, one developing in the central part, and forming the Central Florule 

 and the other developing in the border regions and forming the Border Florule. 



Lastly a few remarks upon the origin of the Chino-Japanese Flora to 

 which belong the Formosan species, will not be out of place made here. 



The coniferce is a comparatively old type now gradually decaying 

 from the world. Looking at the geological history of plants, we see that 

 the coniferae came into existence in the Devonian formation of the 

 Paleozoic epoch, and flourished by and by until the Cretaceous formation 

 of the Mesozoic epoch, when it reached the maximum vegetation. Then 

 gradually decreasing through the Eocene and other formations of the 

 Tertiary, it has come to the present state of vegetation. The present 

 distribution of the conifers is very interesting — each region having the 

 characteristic species of its own. 



We see in the map of distribution 5 ^ that conifers are mostly limited to 

 the northern Hemisphere where they are almost universally dispersed. 

 Fossils belonging to the living genera are very often found in Europe, North 

 America and polar regions, but rather rare in India or China. 



This poorness S) of fossils indicates to us, 1 think, that the conifers 

 existing so abundantly now in China and India are by no means original 

 inhabitants, but emigrants from some contiguous regions that found their 



1) Drude. O: — H;indbuch der Pflanzengeographie, p. 180. 



2) Drude, O:— Berghaus' Physikal. Atlas, Blatt Nr. 45. 



'A) Prof. Yokoyama wrote on the Japanese conifer-fossils in his " Jurassic Plants from 

 Kaga, Hida, and Echizen " in Journ. Coll. Sci. Imp. Univ. Vol. III. p. 15 and 20. 

 According to him, the fossil plants are comparatively poor in conifers, which occupy 

 onl} T 20% of the whole plants. What is interesting to notice, our conifers are also much 

 similar to those of North America in the fossil as well as in the living. China is also poor 

 having only 2Z% of the whole (see Richthofen : China, Vol. IV. p. 214.) In the Indian 

 Mora of Kach and Jabalpur, as Prof. Yokoyama remarks, conifers amount to 29^£ of the 

 whole. In Siberia, on the contrary, conifers are very rich having 10% of the whole. Thus 

 we see that the Conifers, though in their maximum vegetation in the Mesozoic epoch, 

 were not so abundant in China, Japan or India, as in polar regions or North America. 



