Experimental Studies Concerning the Development of the Chicken Embryo

The experiments which are the subject of this paper were started in 1925. It was their original purpose to test whether embryonic malformations or disturbances of development of one or the other kind might be induced by exposing the embryos to electrolyte solutions during the first stages of development. Lippincott and de Puy had reported about experiments in which they incubated eggs lying in shallow distilled water up to the 18th day of incubation. Since the hatchability in these experiments was surprisingly high (28.57 to 47.22%), it appeared probable that a similar method but with Ringer’s physiological salt solution for a medium would yield still better results. Eggs, therefore, were placed in zinc pans coated with paraffin, and enough fluid was poured in to cover the lower half of the eggs. Once a day distilled water was added to compensate for loss by evaporation. The eggs were kept in these . . .