May 3,1924 
PJiotoperiodism of Tephrosia Candida 
449 
Table I .—Comparison of dates of two seasons during which plants in cans No. 1 
to 13, B series, opened their first blossoms 
Can No. 
October 
1922 
1923 
1_ ___ . _ _ 
17 
16 
2____ . . _ __ _ _ 
21 
24 
3_ 
18 
18 
4_ ... . _ _ 
17 
19 
5____ 
25 
24 
6_ __ _ _ . _ 
23 
25 
7____ .. _ 
14 
16 
8_ _ 
15 
(a) 
9_____ 
22 
31 
10. ..... . . . ... _ _ 
14 
16 
11. _ .... ___ 
11 
18 
12__ __ 
19 
24 
13_______ 
16 
15 
Average dates of opening. ..... 
18 
20 
° Date not noted, but was apparently within the preceding week, Oct. 16. 
Table II .—Showing interval between first observance of budding and opening of 
flowers on 20 plants in cans No. 19 to 27, inclusive, B series 
Date budded 
Date 
flowered 
Interval 
between 
budding 
and 
flowering 
Average 
interval 
between 
budding 
and 
flowering 
Aug. 15 ......... 
Oct. 
9 
Days 
55 
Days 
Do. . . . -.. 
Oct. 
10 
56 
Aug. 22 .-. 
Oct. 
9 
48 
Do..... . . . . . 
Oct. 
13 
52 
52 
Aug 29 ..... 
Oct. 
15 
47 
Do ....... 
Oct. 
16 
48 
Do ...-. 
Oct. 
23 
55 
Sept. 5 __ 
Oct. 
16 
41 
Do ___ 
Oct. 
18 
43 
Do .....- 
Oct. 
27 
52 
46 
Do . ....... 
Oct. 
28 
53 
Sept. 12 _ _ ___ 
Oct. 
26 
44 
Do . . . . 
Oct. 
27 
45 
Sept. 26 ... 
Oct. 
23 
27 
Do . . . . . . 
Oct. 
26 
30 
31 
Do . . . 
Oct. 
27 
31 
Do _ _ _ _ _ 
Oct. 
30 
34 
Oct. 3 . .... 
Oct. 
22 
19 
Oct. 10 .. ....... 
Oct. 
31 
21 
21 
Do .. ...-.-.. 
Nov. 
3 
24 
The interval between the noting of budding and flowering averaged 52 days 
for plants budding in the last half of August, 46 days for those budding in the 
first half of September, 31 days for those budding in the last half of September, 
and only 21 days for those budding in the first half of October, when the day is 
12 hours and less in length. As the days shortened, the interval proportionally 
shortened. Although there was a difference of 56 days between the earliest 
and latest dates on which the first buds were observed, all plants opened their 
first blossoms within a period of 25 days. 
Groups 4 and 5, for which these cans were the controls, were subjected to a very 
long daily light exposure which was rapidly reduced. They did not differ in 
treatment until June 6, when the daily light exposure of group 5 was reduced to 
12 hours. Group 4 was subjected to the normal day length, which remains at 
13.2 hours from May 31 to July 11. As was true of the controls, group 4 showed 
