DWARF EGGS OF DOMESTIC FOWL. 327 



a. Length and breadth, length and weight, and breadth and 

 weight are significantly positively correlated in eggs of each 

 group. 



b. Index and weight are negatively correlated. The corre- 

 lation is significant for dwarf eggs with little or no yolk. 



c. In dwarf eggs with small yolks, yolk weight is highly 

 correlated both with egg weight and with albumen weight. 



13. During the two years of maximum dwarf egg produc- 

 tion at the Maine Station plant the proportion of dwarf to 

 normal eggs was one dwarf to each 1,158 normal eggs. 



14. During the last eight years 5.15 per cent, of all the birds 

 kept at the Maine Station plant are known to have produced 

 at least one dwarf egg. 



15. Both the actual dwarf egg production and the number 

 of dwarf eggs per 10,000 eggs is lowest during the winter 

 months. It increases through the spring, reaching a maximum 

 in the early summer. 



16. The production of a dwarf egg is usually an isolated 

 phenomenon occurring only once or twice during the life of a 

 bird. Only 3.5 per cent, of the birds which produced one or 

 more dwarf eggs produced more than two, 



17. A study of all the egg records and the available autopsy 

 records for birds which produced one or more dwarf eggs, 

 shows that, in most cases, the disturbance which caused the pro- 

 duction of the dwarf egg was of temporary character and 

 was not correlated with a morphological disturbance of the sex 

 organs. 



18. Eleven of the 200 dwarf egg producers, however, showed 

 evidence that a permanent disturbance had occurred.. In these 

 cases few or no normal eggs were produced after the dwarf 

 egg or eggs, although nesting records indicate that the ovary 

 passed through normal reproductive cycles. 



19. Five of these cases were autopsied and all of them 

 .showed some pathological condition of the oviduct which inter- 

 fered with the passage of the egg, but did not entirely close 

 the duct. 



20. In normal birds dwarf egg production is most likely 

 to occur during the height of the breeding season. It is not 

 associated with immaturity of the sex organs. 



