4600 Natural and Artificial Selection. 

 4650 Degeneration. {See also L 5800.) 

 4700 Phylogeuy. (See also L 4400.) 



TAXONOMY. 



5000 General. 



[In the ensuing numbers, 5100-7900, a slip for each ordinal name, and a slip 

 for each generic name, is intended to be employed, the names of both 

 orders and genera being arranged alphabetically in a single list, under each 

 class ; if the author mentions the order to which he refers a genus, then 

 in the slip on which the generic name stands alphabetically, the name of 

 the order is to be added in brackets, and under the order, in its alphabetic 

 place, a cross-reference to such genus is to be made. 



On each generic slip, if any new specific name has been introduced into 

 the genus, the symbol " n.sp." should be added after the generic name ; 

 if the genus itself is proposed as new, " n.gen." should be added, i 



5400 Dicotyledons. 



6000 Monocotyledons. 



6500 Gymnosperms. 



G600 Pteridosperms and Cycadofilices. 



6700 Vascular Cryptogams. 



7000 Mosses and Hepaticae. 



7300 Characeae. 



7400 Algse and Schizophyceae. 



7600 Lichens. 



7700 Fungi, Bacteria, and Mycetozoa. 



7900 Plants of which the position is not ascertained by 

 the Slip-maker. 



The Orders and Grenera of Fossil Plants are to be arranged taxonomically 

 with the others, a f or other distinguishing mark being prefixed. 



GEOGRAPHIC DISTRIBUTION. 

 8000 Distribution on Land. 



In this su!)clivisioii it is proposed to use the topo- 

 g-iaphical s^'stem laid down in Geography. 



9000 Plankton (Pelagic Botany). 



Entries are to bo g-rouped under the following areas : — 



9200 Arctic (i.e., all within the Arctic Circle). 



9300 North Atlantic. 



0400 Tropical Atlantic. 



9500 South Atlantic. 



9600 North Pacific. 



9700 Tropical Indo-Pacific. 



9800 South Indo-Pacific. 



9900 Antarctic, i.e., all South of Lat. 60° S. 



