416 THE PRIMITIVE VEGETATION OF THE EARTH. 
and are rich in plant remains while poor in marine fossils. 
Hence it is the Devonian of Gaspé, of New Brunswick, and 
of Maine, with that of eastern New York, which have chiefly 
afforded the plants to be described below; and it is exclu- 
sively in these areas that we find underclays with roots, or 
true fossil soils. Most of the localities of fossil plants in 
the distriets above mentioned have been visited, and their 
plants studied ¿n situ by the writer. The Gaspé sandstones 
were first studied and carefully measured and mapped by Sir 
W. E. Logan. The Devonian beds of St. John's, New 
Brunswick, have been thoroughly examined and illustrated 
by Professor Hartt and Mr. Matthews, and those of Perry 
by Professor Jackson, Professor Rogers and Mr. Hitchcock. 
Professor Hall, of the Survey of New York, has kindly 
communicated to me the plants found in that State, and 
Professor Newberry has contributed some facts and speci- 
mens illustrative of those of Ohio. 
In the Sandstone cliffs of Gaspé Bay, Sir W. E. Logan 
recognized in 1843 the presence of great numbers of ap- 
parent roots in some of the shales and fine sandstones. 
These roots had evidently penetrated the beds in a living 
state, so that the root-beds were true fossil soils, which, after 
supporting vegetation, became submerged and covered with 
new beds of sediment. This must have occurred again and 
again in the process of the formation of the four thousand 
feet of Gaspé sandstone. The true nature of the plants 
of these fossil soils I had subsequently good opportu- 
nities of investigating, and the most important results, in 
the discovery of the plants of my genus Psilophyton, are 
embodied in the restoration of P. princeps. This remark- 
able plant, the oldest land plant known in America, since it 
extends through the Upper Silurian as well as the Devonian, 
presents a creeping horizontal rhizome or root-stock, from 
the upper side of which were given off slender branching 
stems, sometimes bearing rudimentary leaves, and crowned 
when mature, with groups of gracefully nodding oval spore- 
