OLIVEB, ON THE ATLANTIS HYPOTHESIS. 



159 



The niue largest Orders, numerically, of the Swiss Tertiary have 

 t prefixed in the above lists. I estimate that about 40 per cent, of 

 the Japanese phanerogamia are ligneous species. These species are 

 included in 238 genera. 



It ought to be borne in mind that the Japanese Flora has been 

 as yet but imperfectly explored. The area of the Islands is given at 

 about 26G,600 square miles. 



Tlie Tertiary and American States Flora, ^c. — The close analogy 

 subsisting between the Tertiary Flora of Europe and the existing 

 Flora of the Eastern, and especially the Southern States of North 

 America is generally acknowledged. Professors Heer and linger 

 have recently examined critically into this relationship, establishing 

 it upon a wide basis of detailed comparisons. Our Table p. 175 

 shows that 88 genera (Dicots. 74 ; Monocots. 14) are common to the 

 Swiss Tertiary and the South United States Floras ; these belong to 

 73 Natural Orders, of which 52 are represented by identical genera. 

 The foUoAving genera from the above table do not occur in Japan ; 

 those, however, growing in Asia or Europe have * affixed. 



The South United States Flora includes about 836 genera (Dicots. 

 663 ; Monoc. 173), referred to 161 Nat. Orders (Dicots. 134 ; Monoc. 

 27). The total number of indigenous sj)ecies is near 2530 (Dicots. 

 1900; Monoc. 630). Of these about 22 per cent, are ligneous. 



X Taxodvim dubium, Prof. Goeppert says probably occurs in the fossil state in 

 Kamtschatka, {i>ifra,p. 181.) 



