March, 1922] TELLEFSEN — RELATION OF AGE TO SIZE 
129 
Table 9. Measurements in Cross Section of Cortical Root Cells of Cuttings of Trees of 
Salix nigra, Group C 
Number of Tree 
35- 
44, 
46. 
48. 
326. 
327. 
328. 
400. 
404. 
602 , 
604, 
605, 
611 . 
620 
624, 
625. 
628, 
629 . 
630, 
631 
632, 
634 
643 
702 , 
703 
704 
705 
708 
Diameter of Tree 
(Inches) 
. ... 10 + 
. . . . 10 
. . . . 18 
. . . . 10 
. ... 13 
. ... 13 
. ... 13 
. ... 10 + 
. ... 15 
. . . . 20 
. . . . 10 
. . . . 8 
8 
8 
. ... 10 + 
. ... 10 + 
8 
. . . . 8 
. . . . 10 
8-10 
. ... 10 + 
. . . . 10 
. . . . 10 
. ... 10 + 
. ... 10 + 
. ... 10 + 
. ... 10 + 
Average 
Ave. Measure, 
5 Cells 
(Microns) 
25.54x22.88 
22.24 X 30.87 
27.22 X 28.22 
31.54x34.52 
21.91 X 26.56 
27.55 X 26.56 
28.85 X 27.77 
24.57x27.55 
25.89 X 29.21 
28.82 X 27.68 
31.87 X 33.86 
22.91 X 25.23 
29.88 X 37.18 
28.38 X 31.04 
30.21 X 30.54 
28.12 X 30.88 
21.25 X 22.91 
26.56 X 26.89 
24.90 X 27.56 
34.24x26.84 
30.54x26.89 
20.24 X 20.58 
32.87 X 30.54 
33-54 X 34-86 
28.72 X 29.72 
29.22 X 27.56 
34.20x34.87 
32.20x36.85 
.27.28 X 29.16 
Table io. 
Measurements in Longitudinal Section of Cortical Root Cells of Cuttings of Trees 
of Salix nigra, Group A 
Diameter of Tree 
(Inches) 
1 
4 
61.08 X 
3 
16 
43-49 X 
1 
8 
64.74 X 
2 
150.72 X 
I 
148.50 X 
I§ 
80.88 X 
2 
112. 21 X 
I 
86.98 X 
2 
120.35 X 
Ih 
101.59 X 
I 
66.98 X 
I 
112. 21 X 
95-81 X 
Ave. Measure, 
5 Cells 
(Microns) 
3-94 
:2.28 
17.92 
Number of Tree 
76 
302 
308 
707 
710 
714 
715 
716 
717 
719 
733 
746 
Table ii. Measurements in Longitudinal Section of Cortical Root Cells of Cuttings of Trees 
of Salix nigra, Group B 
Number of Tree 
58 
62 
68 
Average . 
Diameter of Tree 
(Inches) 
. . . . 4 
. . . . 4 
. . . . 4 
Ave. Measure, 
5 Cells 
(Microns) 
70.13 X 14.59 
82.33 X 15.27 
95.94x30.21 
82.80 X 20.02 
