1878.] 



Pliyto-Palceontological Investigations. 



225 



and through them the question of the origin of the vegetable kingdom 

 will receive such an answer as is open to human inquiry. 



How is it possible to discover the genetic connexion of Floras 

 following each other in immediate succession ? 



The successive Floras of different ages are not sharply distinguished 

 from each other, but there are the most manifold transitions between 

 them. These transitions are to be found in the common species. It 

 is therefore desirable closely to examine, in the above-mentioned 

 method, the species most frequently met with, and specially to select 

 from the different varieties the progressive and retrogressive forms. 

 By placing together these with other varieties discovered, in a vertical 

 direction (that is, crossing the horizons lying over each other), the 

 Phylogenetic series are obtained, and therewith also the required 

 connecting links of the Floras. 



As examples of the Phylogenetic series, only those of the Oastanea 

 atavia and of the Pinus palceo-strobus*), found by me, are at present 

 known. Other Phylogenetic series which I have discovered will be 

 published at a future time. 



IV. — Results relating generally to the Tertiary Flora. 



My method of procuring fossil plants, and the improved method of 

 investigation on the one part, and on the other the direction of the 

 inquiry which I adopted, have led me to results which are very 

 little in harmony with those obtained by the old method. I can only 

 describe most of the previously determined species as being some of 

 them incorrect, and the others of no value, inasmuch as the knowledge 

 respecting them has been derived from insufficient materials. I shall 

 probably, however, not be in a position to adduce special proof of this, 

 and so correctly to determine which the false species are. On account 

 of much new work, I must be satisfied to refer to it generally, and 

 leave it to future specialists to relieve science from the mistakes which 

 have been made. 



I have found : — 



Firstly, that all the Floras of the earth stand in genetic connexion 

 with the Tertiary Flora. These contain the original species of the 

 recent Flora and plant forms of all parts of the globe. The mixing 

 together of forms of plants is clearly shown, especially in the Miocene 

 Flora, as I at first pointed out in the Tertiary Flora of Austria. 



Secondly, that in each of the recent Floras are to be perceived the 

 elements of their common original Flora. They have, however, been 

 more or less changed, and appear frequently altered into manifold forms. 

 I have given the name of " Florenglieder " (members of a Flora) to 

 these extensively-developed Flora elements. The character of a Flora 



* " Beitrage zur Erforschung der Phylo genie der Pflanzenarten," " Denkschriften 

 der Wiener Akademie der Wissenscliaften," Band xxxviii. 



