VoL. 29 No. 3 
BULGE is 
OF THE 
TORREY BOTANICAL CLUB 
MARCH 1g02 
American Ferns—Ill. Our Genera of Aspidieae 
By Lucrtmen Marcus UNDERWOOD 
The natural arrangement of fern groups has too often suffered 
materially by the systematist insisting exclusively on this or that 
set of characters as primary in importance, to the neglect of others, 
Whereas the sum of characters combined with habit would seem 
to result ina more natural system. John Smith, whose knowledge 
of ferns in cultivation probably exceeded that of any other man, 
emphasized as primary the character of the rootstock, separating 
those genera in which the stipes are articulated to the rootstock 
from those in which the stipes are continuous. On this basis Phe- 
Sopteris and Polypodium, which at Kew are still kept in one genus, 
were distributed at opposite ends of the family. Presl and Fée 
emphasized venation, while Hooker disregarded both these series 
of characters except for sectional (or subgeneric) distinctions and 
made the presence or absence of an indusium and its form primary 
characters in the separation of genera. Mettenius and his followers 
in the later German school have quite largely disregarded most of 
these characters, and the recent treatment in Engler and Prantl, 
while more rational in several other tribes, passes all bounds in the 
Aspidieae in uniting under a single genus forms even more diverse 
than those that exist in some of the Hookerian aggregates. 
It is clear that in the Aspidieae several series of characters 
must be taken into account, and the following would seem to be 
the arrangement in which they appear in the order of their relative 
weight : 
1. Type of venation. 
[Issued 24 March] 121 
