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method at present existing. It would also do away with the un- 

 certainty which now assails the botanist whenever he receives a 

 new fern belonging to this tribe, which has not an indusium evi- 

 dent Where shall it be placed ? Is it a Las tree a % or a Phegop- 

 teris, a Ne ft hr odium or a Gonioftteris ? Such are the questions 

 that arise, and time is wasted, as well as patience, in searching 

 first in one place, then in another, to determine the identity of 

 the new acquisition. 



These suggestions are such as have occurred to me in my 

 own study of this great family of plants. I do not claim for 

 them anything especially original. John Smith, the former 

 curator of Kew Gardens, a most careful and painstaking ob- 

 server, with an immense collection of living species open to his 

 inspection, in his "Ferns, British and Foreign," published in 

 1866, was the first to bring forward the two grand differences in 

 the growth of the stipes from the rhizome, which in his belief 

 divided the true ferns into two sections somewhat analagous to 

 the Exogens and Endogens in flowering plants, although far from 

 being of the same value as the latter distinctions. At the same 

 time the Desmobryous section, with stipes adherent to the stem, 

 and the Eremobryous section, having the stipes articulated with 

 rhizome, do undoubtedly divide the Polypodiacece into very nat- 

 ural groups, in which the indusium is ignored as a distinguishing 

 feature of the tribes, but is retained as a feature of the genera. 

 The only feature which I have proposed, that does not seem to 

 have been proposed previously, is to do away with the indusium 

 even as a generic distinction, and to arrange the species accord- 

 ing to their natural affinities in growth, without reference to the 

 old classification by indusia, except as the indusium is mentioned 

 in the specific description. I have tried to take up the question 

 from the view-point of simplicity and orderliness, and have made 

 an effort to look at it as if there were no traditions behind us to 

 hamper our views, or to make us feel that we must in a measure 

 be guided by them. Something of the same kind will have to be 

 done with the large genus Gymno gramme, a dozen or more spe- 

 cies of which should also be transferred to Diyoftteris. In fact 

 Kuhn has already monographed what he calls the Gymno- 

 grammece and separated them into eight genera. German 

 pteridologists are fond of proposing new genera, which Ameri- 

 can and English botanists, in most cases, hardly feel willing to 

 accept, but we ought not to be too conservative. 



