26 IRVING W. BAILEY AND EDMUND W. SINNOTT 
Table I — Group 2 and Group j 
Total 
Species 
i 
Trees 
•^0 
Shrubs 
1" 
Herbs 
Entire 
Trees 
Shrubs 
E 
Herbs 
E. C. North America 
1.504 
7 
14 
79 
10 
37 
42 
Rocky Mountains 
1,413 
I 
10 
89 
0 
40 
52 
N. Russia 
2 
14 
84 
0 
35 
42 
C. Russia 
1,225 
3 
10 
87 
0 
36 
42 
S. Russia 
2,319 
4 
9 
87 
8 
52 
44 
England 
1,273 
2 
II 
87 
3 
37 
35 
N. E. Germany 
1,166 
2 
12 
86 
0 
29 
45 
3,924 
2 
9 
89 
4 
53 
48 
S. E. Siberia 
458 
2 
10 
88 
0 
45 
44 
Siberia 
1,085 
-2 
0 
10 
87 
0 
0/ 
Kamtschatka 
301 . 
17 
82 
0 
35 
33 
15,024 
2 
41 
43 
S. E. United States 
4.451 
6 
18 
76 
36 
54 
48 
Los Angeles 
831 
3 
16 
81 
18 
58 
45 
Chili 
2,409 
4 
30 
66 
46 
55 
46 
Patagonia 
1,488 
2 
28 
70 
28 
57 
47 
Spain 
4,103 
I 
18 
81 
13 
59 
48 
Italy 
3,069 
2 
10 
88 
18 
56 
40 
2,015 
38 
52 
S. New Zealand 
713 
8 
33 
59 
53 
68 
43 
Simla (mts.) 
989 
13 
25 
62 
53 
60 
38 
20,068 
34 
58 
44 
Among woody plants, leaves and leaflets with entire margins are 
overwhelmingly predominant in tropical and subtropical environments. 
This is very nearly as pronounced among shrubs as it is among trees. 
In cold-temperate regions, on the other hand, trees with entire leaves 
and leaflets are extremely infrequent, and the leaf-margins of shrubs 
are on the average more than half non-entire. Warm-temperate 
regions are intermediate between tropical and cold-temperate ones, 
and the shrubs of frigid habitats resemble those of the tropics in having 
very high percentages of entire margins. 
Among herbaceous plants, higher percentages of leaves and leaflets 
with entire margins occur in tropical and subtropical regions, but the 
contrast between the frigid, temperate, and tropical zones is less well 
marked than among trees and shrubs. 
The somewhat paradoxical behavior of the leaves and leaflets of 
arborescent, as compared with herbaceous Dicotyledons, raises the 
question as to whether the entire and non-entire types of leaf-margins 
are determined by environmental influences, or whether they are 
