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The representation of the various color varieties of Wyandottes among the fowls entered was as follows:

White Wyandottes 805
Buff

205
Columbian

50 Silver

30 Golden

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Since no correlation between egg production and plumage color or pattern has ever been indicated, all of these color varieties have been considered together as members of one breed, the Wyandottes.

Of the 1095 potential records of egg production in these fowls, 903 are available for study. One hundred and seventyseren birds died during the course of their pullet year, five were disqualified for physical abnormalities which prevented them from making a normal record, and the records of ten were omitted for other causes. The remaining birds are those which were apparently normal, and capable of exhibiting whatever inherent capacity they had for producing eggs.

VARIATION IN FIRST YEAR EGG PRODUCTION

IN WYANDOTTES The distribution as regards egg production of all Wyandottes completing a full first year's record in the nine years is given ungrouped in Appendix Table I. This is the raw material on which all calculations regarding annual egg production are based. These same data are given, grouped for treatment into fifteen egy classes in Table 1, which is divided into two parts. In Table la (Columns 1-10) are the actual frequencies for the separate years and the summed frequency representing the distribution in all nine years. The means and other constants have been calculated from the actual frequencies in this table. In Table 1b (Columns 11-20) are the same frequencies, stated as percentages of the total. The percentage columns are directly comparable one with the other.

TABLE 1

FREQUENCY DISTRIBUTION OF ALL WYANDOTTE PULLETS

(A) ACTUAL FREQUENCY

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Eggs laid 1911 1912 1913 1914 1915 1916 1917 1918 1919 1911-19 0- 14

1

1 2 4 15- 29 1

2 30- 44

1 3

1 11 6 45- 59

2
1 3

3 11
60- 74
1 1

1
1

1 9 75- 89

1 3 2

1 28 90-104

9 3 1 8 5 105-119

7 8 10 11 6 4 120-134

6
14

12 15 10 1 82
135-149
9 10 12 12

5 16

6 94 150-164

9 7 14 11 18 30 20 5 11 125
165-179
7 13 12

15
20

23 18 10 12 130 180-194

10 1 8 11 24 18 15 8 13 111 195-209

3 6 6 11 12 10 18 10 9 8.5 210-224 4 4 2 3

11

11 10 1 8 54 225-239

1
3 5 10 3 4 1

32 240-254

1
4 2

1 12 255-269

1
1 2 2

1 7 270-284

3

3 285-299 300-314

1

1 Tot. Pullets 04 67 89 91 151 155 123 80 83 903

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This table is a condensation of the data presented in Appendix Table 1, grouped for convenience into fifteen egg classes. It is to be read as follows: (column 1) In 1911, one pullet laid between 60 and 74 eggs; four pullets laid between 75 and 89 eggs etc.

From Table 1, we may gather some idea of the great range in variability of fecundity in this breed. The greatest range is from 12 to 281 eggs in 1915, where the number of individuals is high, while the range is least in 1914 (79 to 239 eggs) where the number of individuals is low. In general when more individuals are considered more different kinds of egg producers are encountered as might be expected in such a highly variable character. The range in all 903 pullets is 308 eggs, although the great bulk of the birds (80 per cent) are found to lay between 105 and 194 eggs, roughly between 100 and 200 eggs.

TABLE 1

(B) PERCENTAGE FREQUENCY

Tot.

Col. 11

1.1

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1 3.1

Eggs laid 11911 1912 1913 1914 1915 1916 1917 1918 1919 1911-19 0- 14

.7

1.3 2.4 .4 15- 29

.6

.2 30- 4

.71 1.9

1.3 1.2 45- 59 3.0 2.2

1.9

3.6 1.2 60- 74 1.6 1.5 1.1

1.3 .8

1.3

1.2 1.0 75- 89

6.2 4.5 7.9 5.5 .7 1.9 1.6 2.5 1.2 3.1 90-104 6.0 6.7 5.5 6.0 1.9 .8 10.0 6.0

4.8 105-119

12.5 6.0 6.7 7.8 5.3 6.5 8.9 7.5 4.8 7.1 120-134

12.5 10.4 10.1 6.6 9.3 7.7| 12.2 12.5 1.2 9.1 135-149 7.8 13.4) 11.2 13.2 7.9 12.3 4.1 20.0 7.2 10.4 150-164

14.1 10.4 15.7 12.1 11.9) 19.3 16.3 6.3 13.3 13.8 165-179

| 10.9 19.4 13.5 16.5 13.2 14.8 14.6 12.5 14.5 14.4 180-194

15.6 6.0 9.0 12.1 15.9| 11.6 12.2 10.0/ 15.7 12.3 195-209

4.7 8.9 6.7 12.1 7.9 6.5 14.6 12.5 10.8 9.4 210-224 6.2 6.0 2.2 3.3

7.3 7.1 8.1

1.3 9.6 6.0 225-239

1:6 1.5 3.4 5.5 6.6 1.9 3.3 1.3 4.8 3.5 210-254 3.1 3.0 1.1 2.6 1.3

1.2 1.3 255-269

1.1
.71 1.3 1.6

1.2 .8 270-284

2.0

.3 285-299 300-314

.8

.1 99.9 100.0/ 99.7 100.2 100.1 99.8 99.9100.3 99.9 99.9

Columns 11-20 to be read: In 1911, 1.6% of the total pullets laid between 60 and 74 eggs. in 1912, 1.5% of the pullets laid between 60 and 74 eggs. The class in which the mean falls is designated in each year by the frequency printed in bold type. The modal class i. e. the class of greatest frequency, can be determined roughly by inspection.

The percentage distribution for the nine years is shown graphically in Fig. 1.

Fecundity is such a variable trait and the separate years include so few individuals that their curves are likely to show rather large irregularities due in part to the special conditions peculiar to the individual years and in part to the fact that there is a large element of chance in the selection of birds to be entered in the contest.

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Fig. 1. Variation in annual egg production; nine year's records.

The salient features of this curve (Fig. 1) are:

1. It has a single mode in the class 165-179 eggs (theoretically at 170.46 eggs, see Table 2). That is to say more birds lay in the neighborhood of 170 eggs than any other number. The presence of the single mode indicates that this group of Wyandottes, although drawn from many sources, is fairly homogeneous in respect to egg production.

2. The mode is above the mean i. e. the distribution is asymmetrical or skew, and in this case the skewness is negative. Pearl and Surface (1909) noted this tendency toward negative skewness in all of their curves of variation in egg production in Barred Plymouth Rocks and although suggesting that such a tendency might be produced by selection for high egg production concluded that it was probably typical of fowl fecundity in general. That conclusion is supported by the present evidence.

3. The general form of the curve is quite regular, aside from the slight asymmetry noted. Variation in this character appears to be of the continuous type. The rise from zero to the mode is somewhat more gradual than the descent from the mode to the upper limit. On the whole it is a highly orderly frequency distribution. The most suitable mathematical equation for the graduation of the distribution does not require consideration here.

TABLE 2 SUMMARY OF VARIATION CONSTANTS FOR ANXUAL EGG PRODUCTION OF WYANDOTTE PULLETS. COXTESTS OF 1911-1919.

Coefficient Standard of Mean Deviation Variation Median Mode Skewness 1911 | 61 154.66+3.57 42.36+2.25 27.39+1.69 158.33+4.48 165.68 —260+.094 1912 67 153.86+3.65 44.40+2.58 28.85+1.81 157.50+4.39 164.78 -.246+.093 1913 89 148.23+3.30 46.23 +2.33 31.18+1.72 152.68+4.14 161.56 —.288+.078 1914 91 159.80+2.79 39.5271.97 24.73 +1.31 164.32+3.50 172.35 – 343–.074 1915 151 168.62=2.59 47.31 +1.83 28.05+1.17 172.13+3.25 179.13 -222+.063 1916 155 157.77+2.42 44.71 +1.71 28.34+1.17 160.75+3.04 166.70 4.200.+059 1917 123 168.95+2.44 40.25 +1.73 28.32+1.08 170.42+3.07 173.35 4.109+.073 1918 80.146.68+3.15 41.86+2.23 28.54+1.64 145.31+3.96 142.58' +.098+.091 1919 83' 162.42+3.94 53.22 +2.78 32.77+1.89 173.13+ 4.94 194.53-6037.063 Yrs. \903 139.30+1.01 45.32+1.71 28.44+0.48163.02+1.27 170.46 -246+.025

Year N

All i

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