9 
Alabama in latitude, and in longitude from Bohemia to 
the Ohio, we can find no parallel to it in the existing flora 
of the globe. Connected with this subject is the numerical 
proportion which ferns are supposed to have borne to the 
Phaenogamous vegetation, at the period of the deposition 
of the coal strata, as compared with their proportion at the 
present day. Dr. Lindley says, " Two-thirds of the species 
of plants which have been detected in this formation are 
ferns. The earliest flora of the globe was composed of 
ferns, almost to the exclusion of other plants." Burnet 
observes, " The relative predominance of ferns seems to 
have been greater in the coal era than at any other period ; 
from present data they appear to have then formed more 
than three-fifths of the vegetation of the earth." Goeppert 
states that out of 1,792 species of fossil plants known, 
upwards of 524 are ferns. I cannot, however, help think- 
ing that too much weight is given to the proportion they 
now bear in a fossil state, since the experiments of Dr. 
Lindley, to which I shall shortly allude, clearly demonstrate 
that above two-thirds of the vegetation of the present day 
are not capable of resisting submersion in water for two 
years, and, consequently, if submerged now, would leave no 
relics for after ages to decypher. This fact, however, 
while it teaches us the necessity of extreme caution in 
assuming the non-existence of species, because they have 
left no remains, does not invalidate the assumption that 
ferns greatly preponderated in remote ages of the world; 
as an approach to this disproportion between ferns and 
the rest of the flora is even now exhibited in certain tropi- 
cal islands, such as Jamaica, where they form I of the 
Phaenogamous plants; New Guinea, where they are as 28 
to 122; New Ireland, where they are as 13 to 60; and 
in the Sandwich Islands, as 40 to 160. Upon Continents, 
however, they are far less numerous. Thus in Equinoctial 
