oct. i, 1925 Relation of Shape and Size of Eggs to Hatching Quality 689 
Table III .—Mean shape index of eggs whose embryos died in shell and that hatched 
per bird 
' [Eggs laid by 24 Barred Plymouth Rock pullets] 
Pullet No. 
Died in shell 
Hatched 
Difference 
Num¬ 
ber 
Mean shape 
index 
Num¬ 
ber 
Mean shape 
index 
1___ 
20 
76.02±0.53 
32 
76.55±0.16 
0.53±0.55 
2__ 
18 
75.38dh . 38 
32 
75.23± . 15 
. 15± . 41 
3_____ 
17 
77. 71± . 44 
42 
77.51± . 13 
. 20db .46 
4__... 
16 
76.87db . 27 
28 
76.80± . 17 
. 07dz . 32 
5___ 
13 
78.55± . 67 
38 
78.38± . 14 
. 17± . 68 
6___ 
13 
80.43± . 54 
33 
81.51d= .21 
1.08± . 58 
7___ 
12 
74.01± . 77 
34 
74.30± .20 
. 29± . 80 
8___ 
14 
75. 93± . 37 
27 
76.98± .27 
1. 05± . 46 
9_____ 
15 
72.48± . 62 
26 
71.97dt . 14 
.51± .64 
10___ 
18 
77.16± . 43 
31 
75.81± .28 
1.35± . 51 
11... 
16 
73.21± .31 
28 
73.01± . 16 
. 20± .35 
12___ 
13 
73.26± .41 
35 
72.84± . 16 
. 42± .44 
13_____ 
19 
74.03± .22 
22 
74.53± . 24 
. 50± . 33 
14______ 
19 
76.99dh . 20 
37 
76.26± . 13 
. 73± .24 
15____ 
22 
69.46dt . 56 
28 
69. 76± . 17 
. 30± . 59 
16___ 
13 
70.43± .41 
22 
71.22± .21 
. 79± . 49 
17____ 
18 
77.24db .28 
30 
76.62± . 19 
. 62± .34 
18___ 
18 
73.86± .32 
29 
74.31± . 19 
. 45± .37 
19____ 
11 
75.38± .61 
19 
73.83± .24 
1. 55± . 66 
20.... 
18 
76.31± .21 
37 
77.00± . 15 
. 69± .26 
21____ 
16 
77.91± .28 
28 
77.31d= .23 
. 60± .36 
22 ___ 
14 
74.03db .31 
34 
73.*18± . 14 
. 85± .34 
23..... 
18 
74.37± .24 
37 
75.02± . 16 
. 65± .29 
24___ 
28 
78.87± . 16 
30 
78.26± . 17 
. 61d= .23 
The number of eggs per pullet whose embryos died in shell and 
those which hatched varied from 30 to 59, with an average of 47.42. 
The number of eggs whose embryos died in shell varied from 11 to 
28 with an average of 16.44 per pullet. The number of eggs which 
hatched varied from 19 to 42, with an average of 30.98per pullet. 
It is apparent from the data in the last column of Table III that 
there is no significant difference in any individual pullet between the 
mean shape index of the eggs whose embryos died in shell and the 
mean shape index of the eggs which hatched. 
The per cent of fertile eggs which hatched has been determined for 
each oi the 24 pullets and the percentages have been correlated with 
the mean shape index of the fertile eggs of each pullet. The value 
of this correlation has been found to be 0.27 ±0.13. Therefore, the 
mean shape index of a pullet’s eggs does not affect their hatchability. 
WEIGHT OF EGGS IN RELATION TO HATCHABILITY 
In this study, in addition to the 1,253 eggs dealt with previously, 
the records of 1,392 other eggs are available, including 534 laid by 
Rhode Island Red hens, 342 laid by Rhode Island Rea pullets, 148 
laid by Barred Plymouth Rock hens, and 368 laid by Barred Ply¬ 
mouth Rock pullets. 
The data pertaining to the second group of eggs are shown in 
Table IV. For the sake of comparison, the mean weights of the eggs 
set, those which were infertile, those which died early, those which 
died late, and those which hatched are shown in comprehensive 
form. The per cent of fertile eggs which hatched is also shown for 
each group and for each breed. 
