ioo6 



Journal of Agricultural Research 



Vol. VI, No. 25 



An examination of the diagram or of the data given in Table XXII 

 shows that not only is the actual number of dwarf eggs smallest during 

 the winter but that the number of dwarf eggs per 10,000 is also smallest. 

 The irregular fluctuations of the fall are due to the fact that three of the 

 abnormal birds already referred to laid during these months. The 

 small number of normal eggs produced at this season gives great 

 weight to these dwarf eggs in calculating the number of dwarf eggs per 

 10,000. Both the actual number of dwarf eggs and number per 10,000 

 increases through the spring, reaching its maximum in early summer 

 some months later than the maximum for normal-egg production. It is 

 thus shown that the dwarf-egg production is actually highest and also 

 highest in proportion to the normal-egg production during the spring and 

 early summer. 



It thus seems probable that the disturbances in physiology which 

 result in the production of dwarf eggs become more frequent with the 

 onset of the natural breeding season and continue to increase in frequency 

 during this season. The probable nature of these disturbances will be 

 discussed later. 



VII.— DWARF EGG PRODUCTION BY BIRDS WITH NORMAL AND WITH 

 PATHOLOGICAL OVIDUCTS 



The production of a dwarf egg is usually an isolated phenomenon — 

 that is, a bird usually produces only one such egg. This fact, which has 

 already been noted, is easily seen from Table XXIV. 



Table XXIV. — Number of dwarf eggs laid by each bird which produced one or more 



such eggs 



From Table XXIV we see that of the 200 birds which produced one or 

 more dwarf eggs, 178, or 89.0 per cent, produced only one; 15, or 7.5 per 

 cent, produced two; and only 7, or 3.5 per cent, more than two. The 

 figures given by Warner and Kirkpatrick (26) for the birds in the Con- 

 necticut Station laying contest show an even larger percentage (94.11 

 per cent) of the dwarf -egg producers which lay only one dwarf egg. One 



