Preface 



For many years morphology was regarded as a basic discip- 

 line in the study of botany and, consequently, there have 

 been many textbooks dealing with the subject. The pterido- 

 phytes occupied varying proportions of these, and there 

 were even some textbooks devoted to a single group, such as 

 the ferns, within the pteridophytes. However, to the best of 

 my knowledge, no book dealing solely with the pteridophytes 

 has been pubHshed in the western hemisphere since 1936. 

 Some of the old classics have recently been reprinted, but 

 there is a need for a reappraisal of the old theories in the 

 Ught of recent knowledge. Contrary to general behef, the 

 study of morphology is a very live one, and many important 

 advances have been made, on both sides of the Atlantic, in 

 the last decade. Exciting new fossils have been discovered 

 and new techniques have been developed for studying living 

 organisms, to say nothing of the discovery of an entirely new 

 genus of lycopods in the High Andes of Peru. 



Naturally, a book of this kind owes much to those that 

 have gone before, and the most important of these are Hsted 

 in the bibhography. The majority of the illustrations have 

 been redrawn from pubHshed accounts, either in these text- 

 books or in research literature, and this fact has been 

 acknowledged in every case by reference to the author's 

 name. 



I should Hke, also, to acknowledge the help given un- 

 consciously by my colleagues in the Botany School, Cam- 

 bridge, discussions with whom over the years have crystal- 



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