288 CONCLUSION. 



materials as I had before me, and published lately after his 

 death (in the Nederl. Kruidk. Arch., 1863), because, judging 

 from the descriptions, they are not well founded." 



It is indeed well known that there is a tendency among 

 botanists of the present day to increase the number of species 

 (and genera too) on insufficient characters; an error often 

 indeed arising from incomplete specimens, and want of suites 

 of specimens, which would show the modiiications to which 

 they are liable. 



On the limits of the genera of Ferns, it is needless for me 

 to remark here. Every author is entitled to entertain his 

 own views upon the subject. I have endeavoured to main- 

 tain such as may best preserve the natural grouping of the 

 species, and be attended with the least difficulty to the work- 

 ing student. 



It was the intention of the Author, as announced in a note 

 at p. 1 of Vol. I., to have included the OsmundacecB and Ophio- 

 glossacece (generally arranged among the Pseudo-Filices, 

 P^Filld.), or anomalous Ferns ; not numerous indeed; but the 

 fifth volume is sufficiently bulky without them; and the Au- 

 thor is preparing, if his life and health be spared to him to 

 accomplish, a volume, to be entitled "Synopsis Filicum," 

 with ^rif/" characters of the sections, genera, and species of 

 Ferns (omitting all really dubious ones), with general habi- 

 tats, and references, in every instance,for synonyms, more full 

 locahties and general information, figures, etc., to the pages 

 of the present Work ; to which will be added all needful 

 corrections and alterations, also the additional species (not a 

 few) which have come into the author's possession during 

 the twenty years this present Work has been in progress ; 

 and, lastly, including the Schizcsacea, OsmundacecB, Marat- 

 tiacece, and OpJdoglossacece ; thus constituting a needful sup- 

 plementary volume to the ' Species Filicum,' and in itself 

 constituting a handbook, especially useful to ti-avelling pteri- 

 dologists, who would find it impracticable to carry about with 

 them so voluminous a Work as the present. 



Royal Gardenx, Kew, 

 Jan. 1, 1SG4. 



