670 KANSAS CITY REVIEW OF SCIENCE. 
untrue. Such a course of reasoning—which is basing our science on our ignor- 
ance instead of on our knowledge—can hardly be considered in accordance with 
the certainty demanded to establish a scientific truth. A third fact concerning 
the coal flora is, that though the most luxuriant the earth has ever produced, it 
was in its nature utterly unfit to minister to the wants of herbivorous animals. 
A few mandibulate insects may have found sustenance in the foliage, bark or 
wood of some of the vegetable forms of that age, but we have no evidence that 
any higher animal organisms ever grazed on the verdant plains or browsed in the 
luxuriant forests of that age specially noted for the abundance of its vegetable 
productions. ‘The higher animals of this age seem to have been amphibians that 
probably preyed on the lower forms of animal existence. The orders of plants 
that prevailed at that time contribute but little to animal sustenance at the present 
time when herb-eating animals are so extremely abundant. 
The Reptilian Age, which succeeded to the carboniferous, was also charac- 
terized by the production of extensive beds of coal, indicating a flora that in 
some degree would rival that of the preceding age. 
Extensive coal deposits of this age are found in Eastern Virginia, North 
Carolina, England, Scotland, India and China. A considerable change, how- 
ever, had taken place in the vegetable tribes since the coal age proper. The 
Lepidodendrids, Sigillarids and Calamites of the previous age had measurab'y or 
entirely disappeared, and the forest vegetation of the age of reptiles was com- 
posed principally of tree ferns, cycads and conifers. The first of these, which 
had formed so conspicuous a portion of the flora of the previous age, still existed 
in great numbers, forming near two-fifths of the whole flora. The cycads, which 
appear here for the first time, were a family of plants allied on one hand to the 
ferns and on the other to the conifers, and which, in their general appearance, 
resembled stunted palms. Numerous species of conifers appeared during the 
earlier periods of this era. The Odlitic and Jurassic periods were remarkable 
for the abundant gymnospermous forests that existed. As the coal measure 
periods were remarkable for the prevalence of acrogens, so these were noticeable 
for the great number and luxuriance of zymnospermous conifers. But when we 
reach the Cretaceous, the latest period of this era, we find a great advance in the 
development of vegetable organisms. A more radical change in the flora of the 
earth never appeared at any other period in the world’s history. This period 
reveals a type of plants not found in any of the older rocks. Angiosperms, both 
dicotyls and palms, are here found in great abundance. The appearance of a 
cretaceous forest would have been quite modern compared with an) thing that had 
ever appeared before. Among other modern genera might have been seen oak, 
beech, poplar, walnut, hickory, willow, maple, dogwood, sycamore, sassafras, 
tulip-tree, laurel, sweet-gum, fig and myrtle. Many of these genera were repre- 
sented by a considerable number of species that can boast of but one or two at 
the present time. Of this we find examples in the sassafras, sycamore and 
others. It thus appears that many of these genera are but the fragments of a 
much richer flora of an earlier age. When we reach the next age—the Cenozoic 
