Remarks on the Ancient Flora of the Earth. 127 



in the layers of Portland and Purbeck stone, (Geol. Trans, ii. 

 p. 41,) standing upright, and having their concentric formation 

 perfectly preserved. Among the remains of a former age found 

 by G. Mantell, in the strata of the iron-sand of Tilgate Forest, 

 there are also unquestionable remains of plants of this class. 

 Count Sternberg has likewise already described the fruit of a 

 species of juglans or walnut found in the salt-works of Wielitz- 

 ka, the beds of which, we may refer, according to the accu- 

 rate researches of Professor Pusch, to the formation of Lias 

 contemporary with the sandstone and limestone which, to such 

 an immense extent, compose the mass of the Carpathians. For 

 understanding the progressive development of organic bodies, 

 during the different periods of the earth's formation, it is cer- 

 tainly a very important object to fix the limits from which are 

 first exhibited traces of the most perfect organization, of which 

 the members of the vegetable and animal kingdoms are in gene- 

 ral capable. The question as to the first appearance of dicoty- 

 ledonous plants, is of equal signification as that in regard to the 

 first appearance of remains of quadrupeds in the crust of the 

 earth. In the present state of the organic creation, the propor- 

 tions of both classes to the total sum of animals and vegetables, 

 appear regulated according to analogous laws. We, however, 

 do not know so extensively the creations of the present time and 

 of a former age, as to be able satisfactorily to estimate their re- 

 lative numerical value, and we, of course, still stand in need of 

 one of the most important documents regarding the economy of 

 nature in the different periods of her formation. It is, notwith- 

 standing, always of much importance to be able to look into the 

 facts already established, and to observe that the gradual de- 

 velopment of organic bodies in the animal and vegetable kingdom 

 has followed precisely the same progress. While the simplest 

 organised kinds of both kingdoms first appear, we also find re- 

 peated throughout the same gradations, as regards the gradual 

 appearance and increase of the more pei'fectly organised beings 

 in the strata of the earth's crust. Of the four footed animals, 

 it is known that those which first appeared, viz. the amphibia, 

 are the lowest in the zoological scale. While the division of 

 iaurian animals attains a remarkable development in the Jura 



