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J. W. Dawson on the Flora of the Devonian Period. 41 
ART. V.—On the Flora of the Devonian Period in Northeas 
America; by J. W. Dawson, LL D,, E.RS., Prinuival a of 
McGill University, Montreal.’ 
[ConoL.tbep FRoM Vou. xxxv, P. 319.] 
In the course of the preceding pages, I have endeavored to 
notice points of general geological and botanical interest as they 
occurred; and it will now be necessary only to mention a few 
leading results, as to the Devonian Flora, which may be deduced 
from , hospi chewe- Be above recorded. 
1. ts general character, the Devonian Flora resembles that 
of the Carbouiieiis Period, in the prevalence of Gymnosperms 
and Cryptogams; and, with few exce tions, the generic types of 
the two periods are the same. Of thi irty-two genera to which 
the species described in this paper belong, only six can be re- 
garded as peculiar to the Devonian Perio ome genera a 
however, relatively much better represented in the Devonian 
than in the Carboniferous deposits, and several Carboniferous 
genera are wanting in the Devonian. 
2. Some species which appear early i in the Devonian Period 
continue to its close without entering the Carboniferous; and 
the great majority of the species, even of the Upper Devonian, 
do not reappear in the Carboniferous Period; but a few species 
extend from the Upper Devonian into the Lower Carboniferous, 
and thus establish a real passage from the earlier to the later 
Fl The connexion thus established between the Upper De- 
vonian and the Lower Carboniferous is much less intimate than 
q that which subsists between the latter and the true oe 
large part of the difference faeween the Devonian and 
Cachoniterae oras is probably related to different geographi- 
cal conditions. The wid ee flats of the Coal Period do 
not seem to have existed in the Devonian era. The land was 
probably less extensive and more of an upland character. 
the other hand, moreover, it is to be observed that, when in the 
e Devonian we find beds similar to the underclays of the 
Coal-measures, they are filled, not with Stigmaria, but with rhi- 
* Copied from the Quarterly Journal of the Geological Society, Nov., 1862. 
Am. Jour. Sci.—Szcoxp Sexies, Vor. XXXVI, No. 106.—Juxy, 1863, 
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