Sept. 18, 1916 Dwarf Eggs 1009 



when the bird is approximately 2 years old. Dwarf eggs are also pro- 

 duced by birds approximately 3 years old. From these data we see that 

 dwarf egg production, unlike multiple-yolked-egg production, is not 

 associated with immaturity of the bird, but that it is most likely to occur 

 during the height of the breeding seasons in the successive years. These 

 are, of course, the seasons of highest normal-egg production. In the 

 case of a very few of the young birds and in an appreciable percentage 

 of the old birds this is the only season in which the birds are in laying 

 condition. 



B. — POSITION IN THE LITTER 



There is a widespread popular belief that a dwarf egg marks the end 

 of a laying period or litter. This belief has found frequent expression 

 in the literature from an early period to the present day. Konig-Wart- 

 hausen (7) summarizes the belief of Tiedemann (25) as follows: "Er 

 halt die dotterlosen Zwergeier f iir ' Reste von in Eileiter abgesondertem 

 Eiweiss und Kalkerde' nachdem durch Jahreszeit oder Alter das Legen 

 zu Ende ist." To this, however, he adds his own observation, "dass 

 solche Fehlgeburten vielfach bei erstlegendern Huhnern (in meiner 

 Sammlung aus Marz, April, und Mai) stattfinden." Wright (28, p. 579), 

 in his discussion of normal eggs, says: "Of the other kinds of abnormal 

 eggs the very small ones only containing albumen usually occur at or 

 near the end of a batch of eggs." That this relation of the occurrence 

 of a dwarf egg to a particular position in the litter is still somewhat 

 generally accepted is shown by two recent statements. Lewis (9) says 

 that "extremely small eggs are common at the beginning and end of 

 a laying period." The second statement referred to occurs in an unsigned 

 article on "Xenia in fowls" in the Journal of Heredity (29) and is as 

 follows : 



Experiments during recent years show that the eggs of any individual hen tend to 

 become a little smaller as she approaches the end of her laying period, and the last 

 one, it is generally believed, is likely to be a dwarf. 



Since both dwarf eggs and broody hens are most common during the 

 breeding season, it is not unnatural that a relationship between the two 

 is assumed by poultrymen who do not trap-nest their birds. The use 

 of the trap nest, however, soon dispels this illusion. Pearl, Surface, and 

 Curtis (21) say that "the laying of one of these eggs is popularly sup- 

 posed to mark the end of a laying period. This belief is without founda- 

 tion in fact. They may be produced at any time." Warner and Kirk- 

 patrick (26) some years later arrived at the same conclusion after a study 

 of the data collected during two laying contests at Storrs. They sum- 

 marize their data on this point as follows : 



It was found that only two eggs out of a total of 103 indicate a resting period after 

 the production of a small egg. In every other case the small egg was found in an 



