The Formation of the Chalazae and Inner Thin White in the Hen’s Egg

THERE has been a widespread belief that the chalazae and the chalaziferous layer of white surrounding the yolk of the hen’s egg are deposited before the remainder of the egg white. It was thought that a specific secretory mechanism was responsible for this chalaziferous material (Richardson, 1936). Hansen (1933) pointed out that the white is secreted in the magnum (albumen secreting portion of the oviduct) as an apparently homogeneous gel. He found that the chalazae are not visible until the egg has been in the uterus for some time, and from this concluded that the chalazae are formed in the uterus. The present authors have confirmed this observation, and the facts here presented indicate that the chalazae and inner thin white develop simultaneously from this gel by a mechanical segregation of its mucin fibers while the egg is in the uterus. McNally (1933) found that the combined thin fractions of . . .