ioio Journal of Agricultural Research voi.vi.No. 25 



almost uninterrupted series of normal eggs. This seems to prove conclusively that 

 small eggs may be laid at any time during a hen 's laying period and that most small 

 eggs are laid while hens are at the height of production. 



The data used in the present investigation confirm the main part of this 

 statement — that is, dwarf eggs may be produced at any time during the 

 laying period. Our figures do not show that they are less likely to be 

 produced at either end of the period than during its midst, as the above 

 authors seem to imply by their statement that "most small eggs are 

 laid while hens are at the height of production." It is quite possible 

 that they do not intend to make such an inference. Their records show 

 that out of 103 eggs 7 were laid after a resting period of 14 to 25 days 

 and 2 were followed by such a resting period. Our own records for 

 normal birds which produced dwarf eggs and which completed the pe- 

 riod of production during which the dwarf egg was laid show that out 

 of 1 83 dwarf eggs 8 were first and 1 1 last eggs in their respective litters. 

 A further analysis of our data on the position of the dwarf egg in the 

 litter follows. 



A few birds lay practically continuously from the beginning of laying 

 until the first molt. Usually, however, there are well-defined laying 

 periods which alternate with periods of nonproduction. The periods of 

 production vary in extreme cases from two weeks to several months. 

 In the present investigation any period of practically continuous laying, 

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

 relation of the production of a dwarf egg to its position in the litter, it is 

 necessary to standardize the litter for the purpose of summarizing the 

 data from the different cases. If the ordinal number of the day 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 was obtained. 

 The frequency distribution for litter position of dwarf eggs is given 

 below. 



Dwarf -egg 

 Fraction of litter. frequency. 



o -0.099 26 



. IOO- . 199 19 



. 200- . 299 IO 



• 3°°- -399 l6 



.400- .499 13 



•5°°- • 599 2I 



. 600- . 699 24 



. 700- .799 15 



. 800- . 899 10 



. 900- . 999 29 



183 

 Mean= 0.506 ±0.01 5 



Standard deviation = 0.307 ±0.011 



