

4 ELORA OE NEW ZEALAND. [Filices. 



Polypodies into those with naked and indusiate sori is to a great extent artificial ; it separates Polypodiu 

 rugnhmm and Hypolepis tenetta, Ferns which are probably one and the same species ; while Polysticliu 

 venustum and Polypodium sylvaticum also, are very nearly allied indeed ; but, to have avoided this, I must 

 either have given each species a genus to itself, or have distributed them amongst other genera, where they 

 would never have been found by the student, and to which some of them are but doubtfully allied*. 



I have adopted thirty-seven genera in all, which is one for every four species : most of these are ad- 

 mitted by all botanists, and five of them are broken up by most (especially Pteris) : had I adopted all the 

 genera that have been proposed, there would have been one for nearly every Tern in New Zealand. 



In the treatment of the species I feel that I am open to more criticism, inasmuch as I have reduced so 

 very many species proposed by excellent botanists (who have made Perns their especial study) to varieties 

 of better known and more widely distributed plants ; I have not, however, done so without much hesitation, 

 nor until after many years' familiarity with the species. I must refer to Chap. II. § 2. of the Introductory 

 Essay to this Mora, for the considerations involved in this question; and 1 must especially repeat the fact, that 

 I have not only gathered a large proportion of the species myself in New Zealand, but have found them m 

 other countries, have seen them growing under Mr. Smith's care at Kew, have examined and compared far 

 more specimens from New Zealand and elsewhere than any of my predecessors can have done, or than any 

 of my successors are likely to have the opportunity of doing for many years to come. Of all New Zealand 

 plants these are the most variable, and the most difficult to recognize by descriptions without plates or 

 specimens : indeed, without access to a very extensive herbarium it is not advisable to describe supposed 

 novelties amongst Terns. The Natural Order is already encumbered with an unparalleled amount of 

 synonymy; and by the time that general collections shall have been accumulated, and rendered sufficiently 

 complete for satisfactory study, this branch of science will be rendered impracticable, except by the few pro- 

 ficients who have grown up with the growth of the evil : then probably a reaction will ensue, the opposite 

 course will be too eagerly pursued, and the reduction of book species will be carried out with as unsparing 

 a hand as is now employed in their multiplication. 



There are many genera under which I have ventured upon observations that may appear to require 

 confirmation ; as when I state my suspicion that there is but one species of OpMoglossum of the vulgatum 

 group, and one of BotrycUum with decompound fronds, which includes Virginia urn,, Australe, and its allies. 

 These are points upon which my own mind has long been made up, and which I have discussed with various 

 Pieridologists, most of whom, after examining all my materials, have come to the same conclusion. 



Tribe I. Gleicheniacjm, Br.— Capsules 2-4, sessile, bursting longitudinally, completely surrounded by an 

 oblique or transverse striated ring. Gen. I. 



Gen. I. GLEICHENIA, Smith. 

 Involucrum 0, v. e margine frondis revolutas. Capsulce in quovis soro 1-6, sessiles, annulo complete 

 cinctai, longitudinaliter dehiscentes. 



* Had Pteridologists arrived at any conclusion as to the value of the organs of Ferns in a systematic point of 

 view, and had there been any good system of the genera published, I should have adopted it for this work, and 

 given an artificial clavis for the student as well ; but so long as one naturalist relies on the veins for characters, 

 another on the indusium, a third on the rhizome, a fourth draws characters from the number of cells in the elastic 

 rings of the capsules, and a fifth considers the slightest deviation from the assumed typical form of any one of these 

 organs, as sufficient to constitute a genus, it is obvious that the science is retrograding, and must do so till more 

 philosophical principles are adopted. 



