408 Scieniific Intelligence. 



of other evidence. Evidence from these other sources has its 

 doubts, but it is not of so small value as that from plants. This 

 coirjparative want of value is well illustrated by the present wide 

 divergence between Paleophytologists and general Paleontologists 

 with regard to the age of the plant-bearing beds of the Rocky 

 Mountains, the Arctic regions, and Europe. An allusion to the 

 uncertainties of Botanical evidence in the Rocky Mountain region 

 may be found on page 149 of this volume. 



But Prof. DeCandolle makes the evidence from plants of less 

 value, we think, than is reasonable. He says : No one would dare 

 to assert that during the progress of a given bed of Pennsylvania 

 coal, there did not exist somewhere, perhaps far away, an elevated 

 region less moist, on which Angiosperms were already in existence. 

 The supposition is a forced one. For, in Cretaceous and Tertiary 

 times, Angiosperms were the plants of moist lands, their leaves 

 abounding in the coal-formations of those eras ; and it is hence 

 natural that they should have abounded in moist places also in the 

 Carboniferous age, if in existence then along with the Acrogens 

 and Gymnosperms. 



In the Oarboniferous period of North America, the peat-making 

 marshes at times spread from Eastern Pennsylvania to Western 

 Iowa and Arkansas, covering an area of more than 500,000 square 

 miles; and, at the same time, there were dry hills or mountains 

 along the borders of the marshes, in New York, New Jersey, Ohio, 

 Wisconsin, Missouri, Arkansas, through all that long age. The 

 Adirondacks were certainly in existence, and the Green Moun- 

 tains, and the Highlands of New Jersey, and other ridges or 

 mountains beyond the Mississippi. The area of those Carbonifer- 

 ous marshes with their surroundings was large enough, and varied 

 enough in surface, to have borne a fair representation of the flora 

 of that era of approximately uniform climate; and still the 

 streams from the hills conveyed, so far as yet discovered, no 

 leaves of Angiosperms to the marshes that bordered the hills. The 

 Coal-measures of the Arctic bear similar testimony, whether there 

 by migration or not, and so do those of Europe. Further, Permian, 

 Triassic and Jurassic beds overlie the Coal fonuation both m 

 America and Europe and have afforded no remains of Angiosperms. 

 It is from facts like these that geologists have been led to infer 

 that the flora of those lands during the Carboniferous age had 

 characteristics distinguishing it very decidedly from that of other 

 ages ; and to deem it probable that the precursors of the Angio- 

 sperms existed then in a state unlike that of a Cretaceous or mod- 

 em Angiosperm. 



Prof. DeCandolle adds, in the same paragraph, that if fossil An- 

 giospermous plants were found by geologists in any rock " that rock 

 would be at once pronounced of the Cretaceous age," [or of later 

 ^ ry generally 



piams IS noi to be trusted, 

 and make the plants of whatever age the fossil nnimaU present 

 may indicate. The " Cretaceous " plants of the United States are 



