4 
d 
1900 | MECHANISM OF ROOT CURVATURE 33 
indicated at the top of the column. The discussion of this table 
will be taken up in connection with tables IX and X. 
TABLE IX." CONTROL: FOR: TABLE Viki 
STRAIGHT UNINJURED ROOTS SPLIT INTO HALVES AT THE SAME 
TIME AS SOME OF THE BRANDED ONES. 
Hours Both Both Both One One 
Dat Root: One in, : 
rior | ened | SARE | eee ery [aay orem | ceveee | yaeie 
Jan. 27 4 a I 2 
28 4 Pes 2 2 
29 3 I 3 
29 4 205 I 2 I 
30 5 0.5 2 3 
Feb. 1 5 2.5 7 2 2 
2 4 125 3 I 
3 3 1.5 3 
4 3 4 3 
5 i 3 5 
8 4 1.25 I 3 
Apr. 13 8 6 8 
51 10 27 2 5 2 5 
19.6% | 52.9% | 3.9%] 9.8%] 3.9%| 9.8% 
This table shows the results with roots which were straight 
and not branded, but which were split at the same time as 
branded roots shown in tables VII] and X. The lots that are 
directly comparable may be known by looking at the date and 
the column showing the hours after splitting at which the obser- 
vations were made. Thus all the lots in table IX, except one 
on January 29 and one on February 4, may be compared with 
lots in table VIII, 
It will be seen that 52.9 per cent. of the roots shown in table 
IX had both halves of each root curved in toward the cut face 
at the time the record was taken for the table. Sooner or later 
all the halves that grew at all, curved in this way. This latter 
fact the table does not show. The different series may be com- 
pared in several ways to show the effect of the branding ; first, 
as to the number of roots that show a given curve ata given 
time ; second, as to the extent of this curve; third, as to the 
