PREFACE. V J{ 



herbarium the stipes are frequently wanting or imperfect; and, when 

 present, these vessels in dried specimens are often very difficult to 

 distinguish. 



The arrangement of Mr. John Smith appears to be a great im- 

 provement upon that of Presl; and his tribes and genera are better 

 circumscribed, and on the whole much more natural. Having adopted 

 in the present work the greater part of the divisions and genera as 

 established by that author, I may nevertheless take the liberty of 

 stating, that I do not altogether agree with him in the position he has 

 assigned to several genera and species in his system. To him and to 

 Dr. Presl, however, Pteridologists are highly indebted for the light 

 which their investigations have thrown upon a family of plants, the 

 genera of which had become cumbrous and unmanageable by the 

 accumulation of heterogeneous masses of species. 



Of the species which are here characterized as new, some probably 

 have already been published, either as species which I have failed to 

 identify, or in recent works which were not accessible to me. I can 

 only say that I have endeavoured to prevent, as far as possible, such 

 an occurrence, by diligently consulting all the authorities which I 

 could command. And in the large collection of Ferns made by the 

 Expedition, most of them on islands in the Pacific Ocean which have 

 not heretofore been much visited by botanical collectors, and where 

 humidity, heat, and shade, elements conducive to the production of 

 Ferns, are combined in a high degree, surely as large a number of new 

 species as are here proposed was naturally to be expected. 



The drawings for the accompanying atlas of plates, were made by 

 a young artist, Mr. William S. Lawrence, and he also engraved the 

 plates. As it was his first attempt at this kind of drawing, and not 

 being constantly under my supervision, there frequently occurred 

 omissions, or but partial representations of the minor details; such 

 as the greater or less hirsuteness of the stipes, rhachis, and costa. 

 or in respect to other appendages. This will account for the dis- 

 crepancies in some few cases between the plates and the letter-press, 

 in these respects. 



