Preface 



The entries in the Index are arranged so that reference can be made, 

 if necessary, to the complete titles in the Catalogue of Scientific Papers. 

 Generally the author's name together with the date will indicate the volume 

 in which the title of the paper may be found in full. But these clues are 

 insufficient when the paper is anonymous, or occurs in Volume XII or in 

 the additions to Volume VI. They are also at fault for titles marked with 

 an asterisk showing that they belong to previous volumes; in these cases 

 the number of the volume is given in the Index entry in small Roman 

 numerals within brackets. The references have been made as short as 

 possible : thus the number of only the initial page of each paper has been 

 given ; but the length of the paper may be found by reference to the 

 Catalogue of Authors. 



When an error has been found in an author's name in the Catalogue, it 

 is corrected in the Index and a reference made to the error. 



The Index contains references to some papers, of dates earlier than 1884, 

 which were omitted in previous volumes of the Catalogue : these are 

 indicated by an asterisk placed before the date ; the full titles of these 

 papers will be given in the continuation of the Catalogue of Authors. 



When an author's personal name does not appear in the original heading 

 of a paper, no attempt has been made to find the name for the Index; but 

 this will be done for the Catalogue of Authors. 



Entries on the same subject are arranged, so far as possible, in order of 

 date irrespective of the authors' names, with the endeavour to present the 

 subject in the historical form. This grouping of the entries, involving 

 modifications of titles prepared by different Referees, or by the same Referee 

 at different times, has been one of the most difficult problems in the pre- 

 paration of the Index. 



The abbreviations used in the Royal Society Catalogue for the names 

 of the serials have been further shortened for the Index. As the abbre- 

 viations are not uniform in all the volumes, it will be found that the same 

 journal may be indicated by several different abbreviations, but in each case 

 the one selected is that which was used in the volume in which the title 

 of the paper occurs. 



In the case of serials commencing since 1883, the abbreviations adopted 

 in the International Catalogue have been used as a guide. 



