
76 BOTANICAL GAZETTE © [FEBRUARY 
gave expression to the view that differences in food supply may 
account for the facts observed. Schimper’? has a somewhat 
similar view, but explains differences in the vegetation of various 
swamps more along the line of relative ease or difficulty of 
absorption in the swampy soils. Both Nilsson and Schimper 
regard peat bogs as essentially xerophytic. 
In this historical sketch mention should be made of the 
work of Flahault*9, who has projected and begun to execute a 
detailed map of the plant societies of France. Conventional 
color tones are chosen for the various plant societies, and they 
are plotted on topographic contour maps. Robert. Smith*”* 
had just entered upon a similar work in Scotland when death put 
a stop to his labors. So far as the author knows, Flahault has 
not concerned himself particularly as yet with the matter of 
classification. Alb. Nilsson* has recently published some inter- 
esting studies of Swedish plant societies, tracing the order of 
succession of vegetation on cliffs and moors. Still more recently 
Meigen*3 has published a series of short articles, tracing the 
order of succession in a number of plant societies. Besides the 
authors named thus far, Drude™*, MacMillan*s, and Pound and 
Clements have given excellent treatments of the plant forma- 
_ tions in their respective regions. 
7 Op. cit. 18. 
SFLAHAULT, Ch.: Projet de carte botanique forestitre et agricole de la France. 
Bull, Soc. Bot. France 41: 56-94. 1894. Ann. de Géographie 5 : 449-457. 1896. 
9FLAHAULT, Ch.: Essai d’une pes botanique et forestiére de col France. 
Ann. de Gésammpble 6: 289-312. 1897, etc. 
7°SMITH, ROBERT: On the study a plant associations. Nat. Sci. 14: 109-120. 
9. 
H, ROBERT: Botanical survey Spa ae I. Edi ee district. HU. 
North Perthshire district. Scot. Geog. Mag. 16: 385~416; 441-467. 
12 NILSSON, ALB.: Nagra drag ur de Pens vaxtsamhallenas ia ada ea 
Bot. Not. ee enc 123-135. 
MEI PP aniprena tea ek Formationsfolge im Kaiserstuhl. _ Deutsch. 
Bot. hone ia 145~147, e 
™ DRuDE, O.: Deutschlands ees I. Teil. Stuttgart. 1896. 
5 MACMILLAN, C.: Observations on the couligeian of oe along shore at 
Lake of the Woods. Minn. Bot. Stud. 1: 949-10 
76PouUND and CLEMENTS: The shee cae at seit I. General Survey- 
Lincoln. 1898. 



