992 



Journal of Agricultural Research vol. vi.no. 25 



Table VII. — Relative variability of the whole and the several parts of normal eggs and of 



dwarf eggs with small yolks 



NORMAL EGGS a 



Characters compared. 



Shell weight — albumen weight 

 Albumen weight — yolk weight 

 Yolk weight — egg weight 



Difference in 



coefficient of 



variation with 



probable error. 



I. 59±°- 1 7 



. q6± . 16 



i.8s± .14 



Difference 



probable error 

 of difference. 



9-4 



6. o 



13.2 



SMALL-YOLKED DWARF EGGS 



Yolk weight — shell weight .... 

 Shell weight — albumen weight 

 Egg weight — albumen weight. 



20. 81 ±7. 54 

 8. 62 ± 4. 00 

 2. 46±3. 32 



2.8 

 2. 1 



•7 



a From 3,180 eggs laid by flock of 22 Barred Plymouth Rock pullets. 



6 Coefficients calculated direct from data for the 16 dwarf eggs of known yolk weight. 



IV.— INTERRELATION OF THE DIMENSIONS, SHAPE, AND WEIGHT OF 

 EACH CLASS OF DWARF EGGS COMPARED TO THE SAME RELATIONS 

 IN NORMAL EGGS 



We have seen that the dwarf eggs of each group vary greatly in each 

 dimension and in weight and shape. We shall now consider the correla- 

 tion in the variation of the several characters in prolate-spheroidal 1 

 dwarf eggs of each class. It will be determined whether a long dwarf 

 egg is broader or narrower than a short one of the same class; whether 

 a large dwarf egg of any class is longer or broader or both longer and 

 broader than a small egg of the same class; whether a large dwarf egg is 

 longer or shorter in proportion to its breadth than a small dwarf of the 

 same group; and whether or not these relations are the same in the 

 several groups of dwarf eggs and in normal eggs. In the case of dwarf 

 eggs with formed yolk the relation between yolk weight and albumen 

 weight is also studied. 



The correlations studied then are length with breadth, breadth with 

 weight, length with weight, index with weight, yolk weight with egg 

 weight, and yolk weight with albumen weight. On account of the 

 small number of dwarf eggs of known yolk weight, the correlations 

 involving yolk weight were calculated directly from the data given in 

 Table III. In the case of the other pairs of characters the usual correla- 

 tion tables were made for each class of dwarf eggs. These are shown as 

 Tables VIII to XIX, inclusive. 



1 Cylindrical eggs appear to show the same relations among themselves as the prolate-spheroidal eggs, 

 but the number is too small to determine the significance of the relationship. 



