The author measured length and breadth (in tenths of millimeters) of 855 Gull eggs from a large colony on the island of Texel (Eendracht). Frequency curves of length (fig. 1) and breadth (fig. 2) are given, as well as the curves on probability paper (fig. 3). Fig. 4 shows the distribution of the respective relations between length and breadth; the data given by de Vries, Jourdain, and Bau have been added.