“ I acknowledge no authority but that of observation.” — L inn. 
This motto was my governing principle in writing the following 
work on the “ British Ferns and their Allies;” and in adopting it I 
hope that I shall neither be accused of arrogance, neglect of the 
opinion of others, nor yet of unnecessarily varying the details of 
science. Should the reader ask. Why I write at all ? I answer, be- 
cause the only book ever published upon this subject, (Bolton’s 
“ Filices Britannicae,”) has long been out of print; and so much 
difference of opinion exists as to the identity of some species, and 
the arrangement of others, that I thought a plain and practical 
synopsis like the present would be useful to the tyro, if not to the 
practical botanist. 
The materials from which it has been compiled are these : — I 
inspected all the herbaria to which I had access ; gathered wild and 
cultivated fronds wherever I could procure them ; and wrote to most 
of our first-rate botanists for specimens, remarks, and habitats. All 
these being collected, arranged, and studied, they were described and 
engraved without reference to any series of plates or descriptions what- 
ever. I then collated these with the works of Linnaeus, Willdenow, 
Sprengel, Swartz, Pursh, Withering, Smith, Hooker, Liglitfoot, 
Hudson, &c. &c., and wherever there was a difference between myself 
and others I searched again for the truth ; and, if still in doubt, have 
been careful to record the disparity. 
