^g BOTANICAL MAGAZINE. [Vol. xix, 



way in comparatively recent geological times. It is noticeable that the 

 conifers of Pacific North America have some similarity to those of Asia. 

 Taking into account both geological and botanical facts, I am inclined 

 to think that Asian inhabitants had their ancestors in North America 

 or the polar regions in some geological age, possibly in the Tertiary. 



III. On the Existence of a Land-mass between Japan and 

 Formosa with reference to the Floral Formation. 



We all know that land plants are not so easily carried over or by 

 the sea, as by land. So the similarity of flora is mostly affected by the 

 continuation of land. Now there is such similarity between the Japanese 

 and Formosan flora, as would necessitate the conclusion that there must 

 have existed some connection between those two masses of lands. 



What then connected them ? The Liukiu Islands which now connect 

 them in an imperfect manner, like so many stepping-stones between the two 

 larger pieces of land, must not escape our attention both from a geological 

 and botanical point of view. We all know that the flora of the archi- 

 pelago is much like that of Formosa. What, then, is the geological rela- 

 tion between them ? 



Dr. Koto says in his " Geological structure of the Liukiu Curve 2 " that 

 " the Liukiu Curve have three parallel rows, the inner being of neo-vol- 

 canic rocks, the middle of Paleozoic or older rocks, and the outer of Tertiary 

 and Quarternary sediments — the characteristic arrangement of the rocks, 

 probably due to the great depression of the East Sea of China, which took 

 place possibly in the Tertiary period. 3) " He also states about the relation 

 of the Curve to the Asiatic continent .as follows : — The curve is only the 

 top of a mountain range upon a plateau which is covered by the East 

 Sea, which, if seen from the bottom of the Pacific Ocean, might be like 

 the Mongolian plateau behind Quenlun mountains as seen from the plain 

 of China, 4) And the Curve had been (before the depression occurred) a 

 true boundary between the continent and the ocean and the very east 

 extremity of the great Asiatic bank. Dr. Yoshiwara in his "Geologic 



1) Darwin, C. : — On the Origen of species, p. 316. 



2) Dr. Koto, in Journ. Geol. Soc. Toky5, Vol. V. No. 49, p. 1, (1897), calls the islands 

 by the name of the Liukiu Curve, because the archipelago are arranged in curved lines. 



3) Journ. Geol. Soc. Tokyo, Vol. V. No. 49, p. 1 (Japanese). 



4) Journ. Geol. Soc. Tokyo, Vol. V. No. 49, p. 11 (Japanese.) 



