Registration 39 
on the distribution of certain trees. 
Vegetation maps are also being pub- 
lished in Great Britain (see pages 55 
et seq,), Germany, the United States, 
and Switzerland. 
The second kind, species charts, 
shows the actual distribution of a single 
species. On these charts, either the 
different habitats of a rare species are 
marked, or the actual geographical 
limits of its range of growth. For 
example, figure i shows the distribu- 
tion of Gentiana lutea in Wiirttemberg 
and the neighbourhoods In figure 2, 
the distribution of the spruce fir 
[Picea excelsa), on the limit of the 
geographical range in West Prussia, 
is charted I 
1 Eichler, J., Gradmann, R., und Meigen, W. 
Ergebnisse der pflanzengeographischen Durch- 
forschung von Wiirttemberg, Baden und Hohen- 
zollern. Beilage zu Jahresheften des Vereins fiir 
Vaterldndische Naturktmde, 63. Jahrg. Stuttgart, 
1907, S. 135 ff., Karte 6. 
2 Conwentz, H. Forstbotanisches Merkbuch, 
