vm. 
that all that go hy the name of neto discoveries^ were really 
so. If we take Mr. Moore’s useful and laborious Index 
Filicum ” as a test of the numerical statistics of Ferns, the 
number appears great indeed. The eleventh part of this 
Index ” has recently been issued, bringing the Catalogue 
down to the letter C, and to the end of the genus Cuspidaria, 
Thus the work at present only embraces the Genera (alpha- 
betically arranged) of the first three letters of the alphabet 
(A — C). These include 47 Genera and 1069 species ! The 
total of such genera to be recorded are 186, of which about 
one-eighth only have been elaborated, so that if we consider 
the remaining seven-eighths of the genera to possess the 
same proportional amount of species, which may possibly be 
the case, this brings us to 8000 different kinds of Ferns 
described in books by persons worthy of credit from their 
name and character; to say nothing of the multitudes of 
synonyms, which are legion. 
But it must be recollected that Mr. Moore necessarily 
reckons, as species of authors, a great number which he has 
no means of verifying, nor of judging whether they ought, or 
ought not to be rejected, as he has done in the case of many 
others : — and of which there is too much reason to fear that a 
large proportion would come into the latter category. If we 
reckon the number of well-ascertained Ferns at half the 
amount enumerated in the Index Filicum,” viz. at 4000 
species, it will perhaps nearly accord with the truth. 
Nothing will so much tend to a correct knowledge of these 
as accurate figures, published on a cheap scale, as are the two 
Centuries ” now under consideration: — and we have had 
