120 ROYAL SOCIETY OF CANADA 
one-half of the species of the Coal Measures in that state are European; 
a large number, considering that the two regions (Europe and the Mid- 
dle States of North America) are about four thousand miles apart. 
Reasoning from this relation of the species of the Coal Measures in 
Europe and the United States, one might expect a much greater num- 
ber of identical species in the plant beds of the Little River Group if 
these were Coal Measures. Such however is not the fact. 
Sir Wm. Dawson in his “ Fossil Plants of the Devonian and 
Silurian of Canada,” pages 85 and 86, records seventy species of plants 
from New Brunswick (1.e., in this case the Little River Group). Of 
four of these only the generic names are given, but of the remainder, 
fifty-eight species are described as special to the flora of the Plant Beds; 
while six species only are recorded as occurring in Pennsylvania, and 
two others—European—species are mentioned. It would appear then 
that only one-seventh of the species of the Little River plant beds are 
found in the Coal Measures of Pennsylvania, and they mostly in the 
lower part. One would hardly infer from this that the Little River 
plant beds are of the age of the Coal Measures. 
Lesquereaux in his flora of the Maunch Chunk red shale, as it is 
developed in the Mississippi Valley and Southern States, shows numer- 
ous genera of the Little River Group as present there; such as Bornia, 
Calamites, Annularia, Megalopteris, Hymenophyllites, Sphenopteris, 
Eremopteris, Archæopteris, and primitive types of Lepidodendra. These 
are genera of the marsh lands, and these southern and western areas of 
the Maunch Chunk shale presented the conditions necessary to carry 
on to the Pottsville strata typical genera of the Little River plant beds; 
which conditions were not present in the Pennsylvanian or typical 
Maunch Chunk, or at least have not been recognized. 
Here in the New Brunswick region, as in Pennsylvania, were no 
extensive flood plain and lagoon deposits in Lower Carboniferous Time, 
but a prevalence of red sediments and deposits swept from an upland 
region into the sea. The flora of these sediments exhibits little variety, 
and Sir Wm. Dawson’s observations show it to consist chiefly of ferns 
of the genera Archæopteris and Aneimites, and primitive types of 
Lepidodendra, i.e., species with small or obscure bolsters. Such are the 
forms entombed at Perry, Maine, in boulder beds and red sandstones; 
such also are the species found in the Lower Carboniferous deposits of 
the Kennebecasis valley. 
Another cause which may have influenced the removal and reappear- 
ance in a changed form of the marsh-land flora of the Little River 
Group is variation in annual temperature. A change of ten degrees in 
the mean annual summer temperature of a region would have a pro- 
found influence on the vegetation. Greater changes than this are regis- 

