INTRODUCTION xiii 



printed in roman type with indication of their author and the reference 

 to the binomials of the hybrid, , 



A few hybrids designated by a name (not by a formula) are not validly 

 published since they lack a description or are referred to bigeneric hybrid 

 names not described. Their names are also listed in this supplement 

 with the author, and full citation, but the word [nomen] is added before 

 the indication of the parents. Furthermore they are printed in italics. The 

 cross-reference to them lists only the formula (without author), in italics, 

 followed by the word vide, by the invalid binomial with its author and 

 by the indication [nomen]. 



Hybrids designated only by a formula are listed in alphabetical order 

 according to the first parent quoted by the author. Their formulae are 

 printed in bold-face type and provided with the same data as any other 

 new species- 



CATALOGUS LITTEKATURAE 



This catalogue lists the books and the papers published between 1934 

 and 1960 that contain new genera, new species or other novitates included 

 in this supplement. It lists also some few works published before this period 

 which had escaped Christensen's attention, as well as some other works, 

 marked by an asterisk (*), which had been incorrectly or incompletely 

 quoted in the « Index Filicum » and its supplements. I have also added 

 the references to some papers dealing with dates of publications of works 

 of basic importance in pteridology. 



The works are arranged in alphabetical order according to their authors ; 

 the publications of the same author are listed in chronological order and 

 are numbered progressively- The numbers are in continuation to those 

 quoted in the « Index Filicum » and its previous supplements. 



Sometimes the part dealing with ferns of a flora or other work is sup- 

 plied by an author different from that of the whole work. In this case the 

 entry in the catalogue is given under the name of the author of the fern 

 accoxmt ; however, the author (or editor) of the whole work is mentioned 



as a cross-reference. 



Names of authors are in bold-face type, titles of books and papers in 

 italics, and bibliographical reference to the serial or place of publication 

 in roman type. The guide to the citation of botanical literature of the 

 International Code of Nomenclature (edition 1961) is followed in the treat- 

 ment of the various bibliographical data. The abbreviations of the serials 

 are given in the Index abbreviationum periodicorum , 



The year quoted in the catalogue is that of effective publication ; the 

 conventional year given on the title page is not mentioned, when different 

 from the correct one. Particular attention has been paid to the date of 

 publication and in many cases I was successful in establishing the exact 

 date of publication. When I was unable to do so, in absence of proof 

 that the date is unreliable, I have adopted the year quoted on the 

 title page. 



