260 NOTES FROM THE SARAWAK MUSEUM. 



1, 2, 3, etc., each genus with a decimal number following' the 

 family number, each species with another decimal number follow- 

 ing- that of the genus. Let me illustrate this with an example 

 taken from the catalogue of Fishes. 

 Class Pisces = E 

 Order 1. Plagiostomata 

 Sub-order. Selachoidei 

 Fam. Carchariidee = E 1 

 Genus Carcharias = E 1.1 

 Species laticaudus = E 1.1.1 



with specimens a. b. c. d. 

 Species acutus = E 1.1.2. 



with specimens a. b. c. d., etc. 

 Fam. Lamnidee = E 2 

 Genus Lamna = E 2.1. 



and so on. 

 By this means all necessity of check lists, registers and double 

 entries is obviated ; a glance at the catalogue reveals the num- 

 ber of specimens of any given species in the collection, the num- 

 ber of duplicates (if any), the desiderata, the number of species 

 in a genus, of genera in a family, whilst the labels of the indivi- 

 dual specimens with numbers corresponding to the catalogue 

 numbers are equally eloquent. 



In cataloguing zoological or botanical specimens by this 

 decimal system, one meets with a difficulty which does not occur 

 in cataloguing literature, since literature can be grouped under 

 subject-headings which always remain constant, such as Geo- 

 graphy, Geology, Meteorology, etc. ; but every biologist knows 

 that new species, new genera, even new families are constantly 

 being created by the systematist, either from newly discovered 

 forms or by the splitting up of old assemblages (for example 

 the Eastern members .of the genus Sciurus have been recently 

 divided by Mr. Oldfield Thomas into five genera), all of which 

 necessitates the interpolation of new catalogue numbers into the 

 pre-existing series, and I must confess that, as yet, 1 have oeen 

 unable to evolve a perfectly satisfactory means of coping with 

 this difficulty. New species may generally be readily disposed of 

 by being added on to those already catalogued, but new genera 

 can not be so treated, since, by so doing, they may be separated 



