

MR. J. G. BAKER ON THE GEOGRAPHICAL DISTRIBUTION OF FERNS. 



garters of the order, with a suitable highway of communication between the two, that 

 emperafc Asia is so much richer in ferns than any other of our five temperate districts, 

 i o * ire need only contrast the 136 subtropical species added here with the 2 



special added to the European -list in North Africa. Passing from the Himalayas east- 

 ward \ s have a few peculiar species in temperate East China, but the number is very 

 •mall. The Jap.nu e fern-flora is a remarkable one, on account of, latitude considered, 



it 



- no 



Miuthern character. Of the species in the Synopsis, 118 are known to 



dearly as inhabiting the Japanese group of islands, exclusive of the Bonin and Loo-Choo 

 dusters. In latitude Japan is about upon a par with the Spanish peninsula, and conside- 

 rably smaller in area; but the Japanese ferns are to the Spanish as three to one — 118 



specie- against 3D 



We see here well shown, what was indicated before by the British 



list, how that with ferns an insular position may compensate to a very large extent for 



he effect of a higher latitude. Of the Japanese species, 20 are peculiar, 14 restricted to 



Japan and other parts of temperate Asia; we have only 17 out of the 34 European species 



which bell the globe J and the others, at any rate we may safely say 60 species, are cha- 



i 



cteristica 1 iy subtropical, and nearly all of them Malay 



If we classify according to 



their i 



result: 



raphy the peculiar species 



of temperate Asia, the following will be 



the 



1 Restricted to the Himalayas 



5J 



a 



JJ 



the Japanese isles 

 Korea and Siberia 

 East China 



Common to Japan and the Himalay 



)> 



» 



>) 



East China and the Himalay 

 Japan and Siberia or Korea 

 Japan and East China 



Total 



66 

 21 



4 



6 

 1 



2 



5 



9 



114 species 



The most remarkable circumstance thus elicited is the absence of that affinity which 

 might a priori expect between the essentially temperate species of the Japanese and 



Himalayan lists 



"We find, in point of fact, that such an affinity can scarcely be said to 

 have any existence, and that the species which the two floras have in common are the 

 subtropical ones common to Malaya also, and not the characteristically temperate forms. 

 Comparing the list for temperate Asia, as a whole, with that of the two other north tem- 

 perate districts, we find 34 species common to it and both the other two. In addition to 



there are 18 species 



hich are European or North African and Asiatic, but 



American, and eight species which are Asiatic and American, but not Europ 



The 



latt< 



Onoclea sensibilis. 

 *Adiantum p< datum. 

 *Pdl;ca gracilis. 

 *Blechnum serrulatum. 



*Asplenium thelypteroides 

 Neplirodium fragrans. 

 Osmunda Claytoniana. 



* 



cmuamomea. 



