978 Journal of Agricultural Research vol. vi.No. 2S 



serpent, the basilisk, whose breath or look was fatal. The basilisk 

 was sometimes said to have head and legs like a cock. Less definite 

 superstitions which simply regard the "cock" egg as an evil omen have 

 also been common. In some places European peasants cast these eggs 

 behind them over a wall or building to avoid bad luck. In other places 

 they used them as evil charms to avenge themselves on their enemies. 

 A very mild sort of vengeance practiced in some localities was to place 

 one of these eggs among the eggs belonging to a neighbor. This pre- 

 vented his eggs from hatching. A more violent charm was made by 

 breaking the dwarf egg and filling part of the shell with dew collected at 

 dawn from a white thorn tree and then exposing this to the sun. A 

 terrible calamity was supposed to happen to the designated person as 

 the sun drank the last drop of dew. 



On the other hand, these eggs have been considered as a sign of good 

 luck. Pearl (11) reported such a superstition which only a few years 

 ago was accepted by a few credulous country people in some parts of 

 the United States. According to this version of the myth a "luck egg" 

 does not break when thrown over a building, and any wish made by the 

 thrower while the egg is in the air is sure to come true. 



The dwarf, witch, or cock egg has emerged from the age of superstition 

 with the cause for its production inadequately explained. It is the 

 purpose of the present paper to discuss (1) the different types of dwarf 

 eggs in respect to shape and also in respect to contents; (2) the variability 

 in respect to size and shape; (3) the interrelations of the variations in 

 dimensions, shape, and size; (4) the frequency of the occurrence of 

 dwarf eggs compared to normal eggs and of dwarf-egg producers com- 

 pared to birds which do not lay dwarf eggs; (5) the seasonal distribution 

 of dwarf eggs; (6) dwarf -egg production by birds with normal and with 

 abnormal oviducts; (7) the relation of dwarf-egg production by normal 

 birds to the age of the bird and to the position of the egg in the clutch 

 and litter; (8) physiological conditions which lead to dwarf -egg produc- 

 tion; (9) the relation of the production of dwarf eggs to other abnormal 

 phenomena of reproduction which either occur in nature or have been 

 experimentally produced; and (10) the contribution which the study of 

 the physiology of dwarf -egg production makes to our knowledge of the 

 normal physiology of egg production. 



Since February, 1908, the abnormal eggs laid at the poultry plant of 

 the Maine Agricultural Experiment Station have been brought to the 

 laboratory for examination. In the eight years to February, 191 6, 298 

 dwarf eggs are known to have been produced at this plant. The weight 

 of 275 of these was taken, and in 261 of these cases the length and breadth 

 were also measured and the length-breadth index calculated. Of the 298 

 eggs recorded 274 were opened, and their contents were examined. 

 Several of the dwarf eggs were floor eggs and a few were laid by birds on 

 which no egg record was kept. In 251 cases, however, the egg record 



