68 ferns: British and foreigs. 



having no natural affinity with the typical representative 

 of that tribe. I have, therefore, characterized them as 

 a distinct sub-order. Mettenius, in his work on Hyme- 

 itojphyllecE, published in 1861, removes them from the 

 position they have hitherto held between CyatJiece and 

 Gleiclwniece, and places them before Polypodiece, as- 

 signing to them the lowest rank amongst the Ferns ; 

 in their downward relationship they would border on 

 mosses. It, however, appears that as far back as the 

 year 1828 the elder Keichenbach regarded the Hy- 

 mcnopliylfoce as the lowest group of Ferns, and indi- 

 cated their relationship to be with Hejmticw. But to 

 discuss the views of these two authors on this subject 

 would require more space than this work will allow. 



These, with a few others, are the principal changes 

 I have introduced ; more might be made, but as, 

 without being accompanied with full explanations 

 showing my reasons, they might be considered un- 

 necessary, I defer my views on the subject for 

 another and more general work on the genera of 

 Ferns, already alluded to. 



The limited size of this book does not permit me to 

 give descriptions of the species; but in order to assist 

 in referring species to their respective genera, I have 

 given the general characters and a woodcut of each 

 genus, and also the principal synonyms, with refe- 

 rences to one or more published figures. The native 

 country of each species I have given only in its widest 

 sense, as many species have a wide geographical distri- 

 bution, and to state their precise localities would require 

 much space, and is the less necessary, as the special 

 localities of each species are given by Sir W. J. Hooker 

 in his great work, the " Species Filicum," now happily 



