[MATTHEW] CLIMATIC ZONES IN DEVONIAN TIME 153 
would have been intercepted by these ridges. On the contrary the 
sub-deltaic floras (Quaco and Riversdale) are on the south side of 
such ridges. 
That these floras have not been recognized as Devonian, is due to 
the fact that they contain many genera and even species of Carboniferous 
type, rather than those which have hitherto been regarded as the typical 
Devonian genera, such genera being those which occupied the earth’s 
surface at that time in the northern zones where this flora has been 
studied; if we examine a map of the Northern Hemisphere it will be 
seen that all recognized localities of the Upper Devonian land floras 
except those of Pennsylvania—New York highlands and the solitary 
basin of Perry in Maine are north of N. lat. 46° while the so called Car- 
boniferous types of plants occur in strata south of this line. 
We therefore come to the conclusion that these Carboniferous types 
of vegetation, as they have been considered, have had a much earlier 
origin than has been suspected, and have flourished in Devonian areas 
before they became Carboniferous types. One of these areas of growth 
and dispersion has been the peninsula of Nova Scotia where these ancient 
floras developed on and around its pre-Cambrian massif; hence they 
spread themselves in Silurian and Devonian times to the neighboring 
lands of the Appalachian country, to become the well known floras of 
the Pocono and the Coal Measures. 
The result of a review of those floras and their stratigraphical 
relations also brings the writer to the conclusion that there were cli- 
matic zones in Devonian Time, and that the present standard of the 
Devonian flora, which excludes them, is based on plants of a northern 
zone, and chiefly those of northern Europe; also that when the De- 
vonian floras of other parts of the world in the Temperate and Tropical 
zones shall have received attention, a much wider diversity of types will 
be found to have existed in the pre-Carboniferous ages, and the present 
supposed monotony of the Devonian vegetation will be removed. 
