Vol. XI, No. 4 
170 Journal of Agricultural Research 
are too few, double-letter expressions of a descriptive nature have been 
used, one capital and one lower-case letter, the two being joined by a 
parenthesis, as “(Gc).” In some cases, where two factors are respon¬ 
sible for the same result, the same letter, subtended by different numerals 
has been used by Tschermak (1911), and these are retained. The same 
factor often expresses itself in several distinct regions of the plant, such 
as the inflorescence, the leaf axils, etc. When more is known concern¬ 
ing the genetic behavior of some of these factors, two or more of them 
may be found to be absolutely coupled such as (1) 1 and (5), in which 
case matters are simplified by representing them by one factor symbol. 
Table II .—List of Pisum factors, alphabetically arranged , and their corresponding 
character expressions 
No. 
Factor. 
Expression. 
I 
A. 
Salmon-pink or rose flower color. With CD gives reddish leaf axils. 
2 
B. 
Purpling factor plus A gives purple flowers. With CD plus A 
gives purplish leaf axils and stem bases. 
Glaucous foliage, stems and pods (with W); “bloom.” 
3 
(Bl) ... ■ 
4 
(Bt). ... 
Pods with blunt apex. 
5 
C[A].... 
With D gives leaf axil and stem color. 
6 
D. 
With C gives leaf axil and stem color. 
7 
E[A].... 
With F and B gives purple dotting on seed coats; in the absence of 
B gives reddish dots. 
8 
(BO.-- 
Modifies the expression of (Lf) toward earlier flowering. 
9 
F. 
With E and B gives purple dotting on seed coats; in the absence of 
B gives reddish dots. 
10 
(Fa).... 
Axillary flowers, round stems, regular phyllotaxy. 
1 to 2 flowers per peduncle. 
11 
(Fn).... 
12 
(Gc)[A]. 
Yellowish green to grayish brown seed-coat color (weak chromogen 
factor), brown hilum. 
13 
G. ..... 
Green cotyledon pigment. 
14 
(Op)... 
Green pod color. 
15 
H. 
Brightener or inhibitor of expression of Gc. 
16 
I. 
Factor which causes green cotyledon color to fade. 
17 
J. 
With (Gc) gives dark-brown seed-coat color. 
With L2 gives indent peas. 
18 
L(A]... 
19 
l 2 . 
With Li(A) gives indent or dimpled peas. 
20 
Le).... 
Long intemodes; with T gives tall plants. 
Primarily responsible for late flowering. 
21 
(Lf) . . . 
22 
M. 
Brown or maple mottling on seed coat; or “ghost mottling” in 
absence of A. 
23 
N. 
Violet eye on seeds. 
24 
O. 
Green foliage, stems, and pods. 
25 
P. 
Inflated, parchmented, nonedible pods with V. 
26 
Pi. 
With P 2 gives purple pods. 
27 
p 2 . 
With P t gives purple pods. 
28 
(pi)... 
Black-eyed seed-coat pattern. 
29 
R. 
Round, smooth seeds with simple, oval starch grains, low water 
content and with excellent powers of germination under unfavor¬ 
able weather conditions. 
30 
s. 
Pods with seeds separated or free. 
3 1 
T. 
Tall, robust plants, large number of intemodes. 
32 
(Tl). . . 
Leaves with tendrils. 
33 
U. 
Dark self-colored purple seed coat. 
34 
V . 
With P gives parchmented, smooth pods. 
35 
w . 
With (Bl) gives glaucous foliage, pods. 
1 For key to numbers i to 35 in parentheses, see Table II. 
