oct. 1.1925 Relation of Shape and Size of Eggs to Hatching Quality 691 
while among the fertile eggs it is lowest in the eggs which hatched, 
55.25 ±0.10. The difference in weight between these two groups is 
0.26 ±0.21, which is not significant. The greatest variation is 
among the infertile eggs, while among the fertile eggs the relative and 
absolute amounts of variation are much the same in the three groups. 
Here, again, as in the case of the other four groups of birds, there is no 
evidence of any significant differences among the weights of eggs 
whose embryos died early, those whose embryos died late, and those 
which hatched. 
Table V.— Incubation results of eggs for different weight classes 
[Eggs laid by 24 Barred Plymouth Rock pullets] 
Weight 
Number set 
Infertile 
Died early 
Died late 
Hatched 
Grams 
46.00 to 46.99„__„„. 
2 
1 
1 
47.00 to 47.99_ 
4 
I 
1 
2 
48.00 to 48.99_ 
7 
2 
i 
1 
3 
49.00 to 49.99. 
11 
2 
1 
3 
5 
50.00 to 50.99.... 
13 
3 
3 
2 
5 
51.00 to 51.99___.... 
28 
4 
2 
5 
17 
52.00 to 52.99. 
77 
7 
6 
14 
50 
53.00 to 53.99.... 
164 
12 
14 
32 
106 
54.00 to 54.99. 
218 
19 
22 
- 48 
129 
55.00 to 55.99... 
227 
21 
20 
52 
134 
56.00 to 56.99... 
196 
17 
16 
42 
121 
57.00 to 57.99___ 
168 
11 
20 
43 
94 
58.00 to 58.99.. 
81 
8 
7 
16 
50 
59.00 to 59.99.... 
29 
3 
4 
8 
14 
60.00 to 60.99__ 
13 
2 
4 
3 
4 
61.00 to 61.99... 
6 
1 
1 
1 
3 
62.00 to 62.99. .. 
3 
1 
2 
63.00 to 63.99. 
2 
1 
1 
64.00 to 64.99 . 
1 
1 
65.00 to 65.99. 
2 
1 
1 
66.00 to 66.99 _ . 
1 
1 
Total__ 
1,253 
115 
121 
274 
743 
Mean weight.. 
55.28±0.04 
55.13±0.18 
55.51dh0.15 
55.31±0.10 
55.25=1=0.05 
Standard deviation.. 
2.22d= .03 
2.82± .13 
2.37± . 10 
2.35dh . 07 
2.22± .04 
Coefficient of variability. 
4.20± .06 
5.12db .23 
4.27db . 19 
4.25± . 12 * 
4.02d= . 07 
The same data as shown in Table V are grouped in Table VI in 
three classes of weight increments, low (46.00 to 52.99 grams), 
medium (53.00 to 59.99 grams), and high (60.00 to 66.99 grams). 
Table VI. — Incubation results of eggs for groups of low , medium , and high weight 
classes 
[Eggs laid by 24 Barred Plymouth Rock pullets] 
Weight 
Number 
set 
Infertile 
Died 
early 
Died 
late 
Hatched 
Per cent of 
fertile eggs 
hatched 
46.00 tn 52.09 
Grams 
142 
19 
13 
27 
83 
67.48±2.04 
53.00 to 59.99. 
1,083 
28 
91 
103 
241 
648 
65.32=1:1.35 
60.00 to 66.99.. 
5 
5 
6 
12 
52.17=L9.46 
