INSTEUCTIONS. 



The present volume consists of three parts : — 



(a) Schedules and Indexes in four languages. 

 {b) An Authors' Catalogue. 

 (c) A Subject Catalogue. 



The Subject Catalogue is divided into sections, each of which is 

 denoted by a four-figure number between 0000 and 9999. These 

 numbers follow one another in numerical order, but all the 9999 

 numbers are not used, for it is intended to fill up the gaps by interpola- 

 tion of such additional sections as may be required for additions to the 

 system of classification in futm-e years. 



To enable the reader to find these numbers quickly, the first or last 

 number on the page is repeated at the head of the page. In looking 

 up a subject, these immbers, which are called Registration numbers, 

 should be used instead of the ordinary pagination. These Registration 

 numbers serve to divide up the subject into sections, each of which 

 deals with related matter. Thus, papers dealing with fruit will be 

 found grouped together in the section 2280, the dicotyledons in 5400, 

 geographic distribution in 8000, and so forth. This will enable a 

 worker on a particular subject to find the various papers dealing with 

 that subject gi-ouped together. 



There are two ways of finding the papers relating to a particular 

 subject. One is to study the Schedule, The reader will in most 

 cases be able to decide in which group the papers on a particular 

 subject are likely to be indexed. The other course is to consult the 

 index to the Schedule. The numbers given in this index can be used 

 either as a reference to the Schedule, or as indicating the position 

 which the given subject oc(-upies in the Subject Catalogue. Thus, in 

 the index to the Scliedule, (jlermination is given as 3750. Accordingly, 

 references to (jermination.will be found in the Subject Catalogue under 

 the Registration number 3750. 



