XXxXli INTRODUCTION. 
and in comparing this flora with those of other countries a 
resemblance is pointed out between the Japanese plants and 
some species described by Heer from Siberia and Spitzbergen. 
Nine years later Matajoro Yokoyama’ contributed a paper on 
the Jurassic plants of Kaga, Hida and Echizen, and adds a list 
of species from these localities. At a later date* he gives a 
much fuller account of this exceedingly interesting flora; and 
a detailed comparison is instituted with floras of other countries, 
the Jurassic floras of Siberia, Spitzbergen, the Yorkshire coast, 
Russia, China, India and Australia, also with the Wealden of 
Europe and the infra-Liassie of Tongking. 
A reference is made by Lester Ward? in his ‘‘ Geographical 
Distribution of Fossil Plants”? to Yokoyama’s earlier paper, and 
the suggestion offered that possibly these Japanese plants may 
prove to be of Lower Cretaceous age, and that the reference by 
Godfrey of the Kiushin leaf-beds to a Cretaceous horizon may 
have been correct. The evidence afforded by the ferns is certainly 
in favour of Ward’s suggestion. 
In 1890 Nathorst® made an important contribution to our 
knowledge of Japanese paleobotany. The plants from some of 
the localities are compared principally to Wealden species, and 
from other places there seems to be a mixture of Jurassic with 
Wealden and Urgonian species. 
Although the titles to the papers of Geyler and Yokoyama 
lead us to expect floras of distinctly Jurassic facies, we shall 
have occasion to point out in the description of certain English 
Wealden species a striking similarity, if not specific identity, 
between them and some of the Japanese plants. 
The following list includes the plants mentioned by Yokoyama 
and Nathorst :— 
1 Bull. Geol. Soe. Japan, pt. B, vol. i. No. 1, 1886. 
? Journ. Coll. Sci. Japan, vol. iii. 1890, p. 1. 
3 U.S. Geol. Surv. Ann. Rep. No. 8, p. 789. 
* Quart. Journ. Geol. Soc. vol. xxxiv. 1878, p. 546. 
5 Denksch. k. Ak. Wiss. math.-nat. Cl. vol. lvii. 1890, p. 43. 
