Page:Popular Science Monthly Volume 81.djvu/377
377
THE INHERITANCE OF FECUNDITY
which carry the excess production factor L 2 are heterozygous in respect to it.
We have fecundity practically determined, then, by two physio- logical factors, one of which is sex-correlated in its inheritance and the ether not.
Table II
Showing Some Besults of Mating Together Barred Plymouth Bock Males and Barred Plymouth Boclc Females of Different Fecundity Genotypes.
Summarized Data
Distribution of Daughters in Respect to Winter
Egg Production
Matings
Over 30
Under 30
Class
Eggs
Eggs
Zero Eggs
dVLiL* • flih X 9/L1L2 • Fhh (high
Observed
21
30
8
producer).
Expected
22.1
29.5
7.4
Average winter egg production in each
class.
48.85
16.34
tffLiLi ¦ flih X 9/IaL 2 • FLih (high
Observed
21.5*
16.5
producer).
Expected
19
19
Average winter egg production in each
class.
50.38
16.69
—
dVLiLs ¦ flih X 9 9 of all types taken
Observed
51.5
62.5
11
together.
Expected
51.45
62.5
11.05
Average winter egg production in each
class.
47.94
15.34
tffliLi • fliU X 9/L1L2 • Fhh (high
Observed
92.5
103.5
7
producer).
Expected
101.5
101.5
Average winter egg production in each
class.
54.19
15.52
tffliLi • fliLi X QfLiLt ¦ FLih (high
Observed
111
6
producer).
Expected
117
Average winter egg production in each
class.
56.47
20.33
—
&fliLi • fliLi X 9 /Life • Fhh (low pro-
Observed
29
23
2
ducer).
Expected
27
27
Average winter production in each class.
47.93
15.30
cffliLi ¦ fliLi X 9 9 of all types taken
Observed
243
149
10
together.
Expected
255.5
146.5
Average winter egg production in each
class.
53.67
15.37
dVLiLj • fliLt X 9/LiLi • Fhh (high
Observed
20
6
3
producer).
Expected
21.75
7.25
Average winter production in each class.
56.90
24.17
tffLiLi ¦ fLih X 9 9 of all types taken
Observed
19
16
together.
Expected
17.5
17.5
Average winter egg production in each
class.
55.47
18.3
—
c?fl\Li ¦ flih X 9 9 of all types taken
Observed
8.5
15.5
5
together.
Expected
10.25
14.5
4.25
Average winter egg production in each
class.
60.50
12.26
The accordance between observed fact and theoretical expectation on this interpretation of the results is shown in the following tables
- The records of i refer to birds whose winter production record was exactly
30 eggs. Each one of the few birds of this sort is divided between the "Over
30" and the "Under 30" classes.
