THE PRIMITIVE VEGETATION OF THE EARTH. 
BY J. W. DAWSON, LL. D. 
TWENTY years ago scarcely anything was known, even to 
those engaged in the study of vegetable fossils, of a land 
flora older than the great coal formation. In 1860, Goep- 
pert, in his Memoir on the plants of the Silurian, Devonian, 
and Lower Carboniferous, mentions only one land plant, and 
this of doubtful character, in the Lower Devonian. In the 
iddle Devonian he knew but one species; in the Upper 
Devonian he enumerated fifty-seven. Most of these were 
European, but he included also such American species as 
were known to him. The paper of the writer on the Land 
Plants of Gaspé was published in 1859, but had not reached 
Goeppert at the time when his memoir was written. This, 
with some other descriptions of American Devonian plants 
not in his possession, might have added ten or twelve spe- 
cies, some of them Lower Devonian, to his list. In the ten 
years from 1860 to the present time, the writer has been 
able to raise the Devonian flora of Eastern North America to 
one hundred and twenty-one species, and reckoning those of 
Europe at half that number, we now have at least one hun- 
dred and eighty species of land plants from the Devonian, 
besides a few from the Upper Silurian. We thus have pre- 
sented to our view a flora older than that of the Carbonifer- 
ous period, and, in many respects, distinct from it; and in 
connection with which many interesting geological and 
botanical questions arise. 
Geologists are aware that in passing backward in geologi- 
cal time from the modern to the Paleozoic period, we lose, 
as dominant members of the vegetable kingdom, first, the 
higher phenogamous plants, whether exogenous or endoge- 
nous; and that, in the Mesozoic period, the Acrogens, or 
(474) : 
