Physiology of Reproduction in Domestic Foivl 351 



been laid the weiglyis of the eggs were no longer taken. There 

 seems to be no particular reason for reproducing here more than 

 the weights of the first dozen eggs shown in Table II. In general 

 it will be seen that all of these eggs were below the average for the 

 breed in size. 



WHAT IS THE CHARACTER OF THE PROGRESSIVE CHANGE TOWARDS 

 THE NORMAL IN THE SHAPE OF THESE EGGS ^ 



In order to answer this question recourse must be had to analyt- 

 ical treatment of the data set forth in Table I. Such analysis may 

 best be begun by exhibiting graphically the changes in the different 

 dimensions of the successively laid eggs. The length and breadth 

 may be considered first. In plotting these dimensions only the 

 first 25 eggs are taken. The reasons for stopping these diagrams 

 at this point are the following: (i) To get the whole 87 eggs into 

 a single text figure involves such a reduced scale as practically to 

 destroy the effectiveness of the diagram for analytical discussion. 

 (2) The dimensions of the eggs after the 25th fluctuate up and 

 down about what is practically a straight line. This being the 

 case it is not necessary in each of the diagrams to carry the line 

 out to the end of the data of Table I. 



The lengths of the first 25 eggs are shown graphically in Fig. i. 

 In this diagram the abscissae denote the ordinal position of the 

 eggs in the whole series laid. The ordinates denote the length of 

 the eggs in millimeters. 



From the diagram it appears that: 



1 The length of the eggs decreases very rapidly in the first 5 

 laid. 



2 The rate of decrease in length becomes progressively slower 

 with successive eggs. 



3 It results in consequence that the line of plotted lengths 

 (disregarding chance fluctuations) is decidedly curved at its begin- 

 ning, but approximates more and more to a straight line as it 

 proceeds. 



The breadths of the first 25 eggs to be laid by hen No. 183 are 



