MAINE AGRICULTURAL EXPERIMENT STATION I9II 2/9 



production of any month in the year. On the contrary, the 

 mean production in all but two of the months actually decreased 

 during the period of selection. So far as there was any change 

 whatever in variability in monthly egg production during the 

 period when selective breeding was practiced, this change was 

 not in the direction of a reduction as a result of the selection, 

 l)ut, on the contrary, there was an actual increase in variability 

 in all but one month of the year, and here the plotted variabil- 

 ity line did not sensibly deviate from the horizontal. 



The present statistics show no bad eli'ect on egg production 

 in the winter months (November to March) of keeping birds 

 in large and crowded flocks (up to the limits included in the 

 present study). On the otlier hand, overcrowding tends dis- 

 tinctly to lower summer (and to a small extent spring) egg 

 production. It is chiefly as a result of this effect on summer 

 production that the mean annual production is lower in the 

 large flocks. The excess of relative variability of egg produc- 

 tion of the larger flocks (100 and 150 birds) over the smaller 

 (50 and 100 birds) observed in the annual records is found 

 upon analysis to be on the whole fairly evenly distributed over 

 the whole year. In the period of the year in which there is 

 the heaviest production, such environmental differences as are 

 implied in the different flock sizes in the experiment do not 

 appreciably affect the relative variability of production. 



HOW AN EGG IS MADE. 



In connection with other studies on egg production an inves- 

 tigation has been made regarding the physiology of the process. 

 The question here proposed is as to how an egg is manufact- 

 ed in the body of a hen. During the past year a paper has 

 been published from the Department dealing with the formation 

 of the albumen or white of the egg. The chief results were 

 as follows. 



The Physiology of the O^'iditct or Bog Tube. 



After entering the infundibulum or mouth of the egg tube 

 the yolk remains in the so-called albumen or white secreting 

 portion of the oviduct about three hours and in this time 

 acquires only about 40 to 50 per cent by weight of its total 



