122 THE VICTORIAN NATURALIST. 



date of the observation ; where the object is drawn I often merely 

 put the number of it, the drawings being numbered consecutively. 

 This can also serve as an index to any calendars that may be 

 kept ; for calendars, if lengthy, or not arranged systematically, 

 require indexing ; it is only necessary to add the number or page 

 in the calendar to tlie entry. I would also point out that it has 

 been my practice to enter in the index each object once only 

 (not every time it is observed or noted in the diary), unless any 

 subsequent matter of importance with reference to it should 

 transpire, and then an additional date or page to the original 

 entry is all that is required : it is not necessary to enter it again 

 unless the line should be filled up with references, then a note to 

 " see below " should be added, and also to the second entry to 

 " see above," but this will not occur very often. It may and 

 does sometimes happen that a second entry is made inadvertently ; 

 if so, notes to see above and below should be made. Any ruled 

 MSS. book can be used for the purpose of an " Index Rerum," it 

 is only requisite that it should contain a sufficient number of 

 leaves to enable you to devote six of them to each letter of the 

 alphabet, and be large enough for all future requirements. 



Some may think I am exaggerating the importance of an index 

 to observations, but I have found it very useful in working — 

 indeed, I may say, almost indispensable. To give you some idea 

 of the utility of it, allow me to give an illustration of what might 

 happen. Most of the botanists of the Club possess, I have no 

 doubt, Baron von Mueller's valuable " Key." Now suppose, 

 instead of being systematically arranged, the descriptions of the 

 various species of plants had been printed one after another, 

 say, in the order in which they were made known to science, or 

 in any other irregular manner — no two species of the same genus 

 nor no two genera of any order within many pages of one 

 another — and there was no index, of what use would the book 

 be ? And, further, suppose a book contained descriptions of the 

 various species of the fauna as well as those of the flora, all mixed 

 up in inextricable confusion (as in mine and I daresay many 

 diaries) of what use would it be, even if it contained everything 

 we wanted to know, if it had no index ? With one it would be 

 invaluable. Likewise an index will transform any records of 

 observations from a heterogeneous mass of items into an orderly 

 and accessible storehouse of information. 



I hope you will not think that I wish to be didactic, for there 

 are many members of the Club far more fitted to be so than I am, 

 but the incentive to write this paper came from some of the 

 members who have seen my calendar and my method of rendering 

 my observations available at any time, so I thought my experience 

 might be of some interest and use to you. If anyone is thereby 

 induced to follow my example and so increase the value of their 

 work, I shall not regret having broughtthe subject under your notice. 



