DWARF EGGS OF DOMESTIC FOWL. 3II 



A few birds lay practically continuously from the beginning 

 of laying until the first moult. Usually, however, there are 

 well defined laying periods which alternate with periods of 

 non-production. The periods of production vary in extreme 

 cases from two weeks to several months. In the present in- 

 vestigation any period of- practically continuous laying, what- 

 ever its length, is considered a litter. In order to determine 

 the re 1 ation of the production of a dwarf egg to its position in 

 the litter it is necessary to standardize the litter in order to 

 summarize the data from the different cases. If the ordinal 

 number of the days in the production period be divided by 

 the whole number of days in the period, the resulting fraction 

 will represent the position in the litter of an egg produced on 

 that day. By this method the litter position of each dwarf 

 egg produced by a normal bird which completed the litter wa^r 

 obtained. The frequency distribution for litter position of 

 dwarf eggs is given below. 



Fraction of litter. Dwarf egg frequency. 



0-.099 26 



.100-.199 19 



.200-. 299 10 



.300-.399 . . 16 



.400-.499 13 



•500-.599 21 



.600-.699 24 



•700-.799 15 



.800-.899 10 



.900-.999 29 



183 

 Mean — .506+. 015 

 Standard deviation — .307 + .011 



This distribution is shown graphically in Fig. 54. 



The irregular fluctuations of the frequency curve for the 

 litter position of dwarf eggs are not greater than the expected 

 fluctuations of a random sample of the same size drawn from 

 a population evenly distributed over the range. 16 The present 



"For mathematical proof, see original paper. 



