March, 1922] 
TELLEFSEN — RELATION OF AGE TO SIZE 
Table 15. Measurements in Cross Section of Endodermal Root Cells of Cuttings of Trees of 
Salix nigra, Group C 
Ave. Measure, 
Number of Tree Diameter of Tree 5 Cells 
(Inches) (Microns) 
35 
T n _1_ 
11-45 X 9.62 
44 
11-95 X 9.90 
I ^ 
14. 1 1 X 10.97 
327 
13 
7.74 X 8.96 
328 
13 
10.62 X 7.77 
400 
10 + 
9.96 X 14.77 
404 
15 
8.61 X 7.61 
602 
20 
9.96 X 9.15 
611 
8 
8.79 X 9.29 
624 
10 + 
11.79 X 8.30 
625 
10 + 
8.80 X 9.79 
628 
8 
9.63 X 12.28 
630 
10 
9.96 X 9.13 
631 
8-10 
8.80 X 11.29 
632 
10 + 
1 1.79 X 8.80 
634 
10 
10.96 X 9.30 
643 
10 
8.96 X 9.29 
704 
10 + 
1 1.95 X 9.30 
Average 
10.32 X 9.64 
Table 16. Measurements in Cross Section of Phloem Root Cells of Cuttings of Trees of 
Salix nigra, Group A 
Ave. Measure, 
Number of Tree Diameter of Tree 5 Cells 
(Inches) 
(Microns) 
76 
1 
9.96 X 7.63 
306 
3 
6.97 X 5-97 
308 
1 
8 
6.80 X 6,97 
321 
3 
re 
9.62 X 6.97 
340 
—I 
6.64 X 7.70 
343 
5.91 X6.64 
364 
—I 
7-63 X 5.97 
606 
2 
7.80x7.63 
608 
2 
7.96 X 7.63 
636 
T 1 
8.04 X 7.63 
640 
I 
7.64 X 7.97 
733 
7.96 X 6.97 
7-82 X 7.14 
Table 17. Measurements in Cross Section of Phloem Root Cells of Cuttings of Trees of 
Salix nigra, Group B 
Ave. Measure, 
Number of Tree Diameter of Tree 5 Cells 
(Inches) 
(Microns) 
58 
• 4 
6.76 X 6.40 
62 
4 
5.64 X 6.64 
68 
4 
6.30 X 7.63 
405 
4 
7.70x7.63 
609 
4 
7.96 x 7.63 
633 
• • • • 4 
6.97x7.13 
635 
5 
8.07 X 7.96 
641 
6 
6.68 X 7.63 
642 
5 
8.13 X 7.30 
700 
5 
6.30 X 6.30 
7-05 X 7-22 
