British ferns (Filicopsida)

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L. Watson and M. J. Dallwitz

Contact information

L. Watson (taxonomy) —

M. J. Dallwitz (computing) —

Conditions of use

Applications of this package (including the duplication of text and images) are encouraged, without fee, provided copies are not made or distributed for direct commercial advantage and the source is acknowledged in publications of all kinds. We would appreciate being informed of such applications.

Our JPEG representations of J.E. Sowerby’s pleasant, hand coloured engravings were designed for convenience of distribution and screen display, and are less sharp than the high resolution TIFF images from which they were generated. The latter have been retained, and could be made available for worthwhile applications.


The database contains no original observations; the descriptions were merely compiled from readily accessible sources. Unlike those from many parts of the world, the British flora and fauna have been studied so extensively that, for many groups, it is possible to construct a useful database entirely from the literature. However, standard taxonomic publications are poor sources of reliable comparative data, and practical testing against living and/or herbarium material is sure to reveal errors and other inadequacies in the descriptions, and hence in the key. We would appreciate having these pointed out, so that they can be corrected without delay; and we would particularly like to hear from people interested in contributing to further development of the package. In addition to improving the character list and adding character and taxon illustrations, this could include extending the geographical coverage, or preparing separate accounts for other regions.