Abstract THERE are four distinct layers or divisions of albumen in the laid egg. These are: the chalazae which are attached at the poles of the yolk, the inner liquid layer surrounding the yolk, the dense or middle thick layer, and the outer thin or fluid layer. Approximately one fourth of the total albumen of a normal egg is found in the outer layer, 50–60 percent in the thick layer, and the remainder in the inner thin and chalaziferous areas. The principal difference in the thick and thin layers is the presence of large amounts of mucin in the thick layer, which accounts for its higher viscosity. Virtually all of the protein of the albumen of the egg is formed in the magnum or upper part of the oviduct. The egg then moves on to the isthmus where the shell membranes and some water are added, and then on to …