II. On the development of the great omentum and transverse mesocolon

The paper begins by quoting the two usually accepted descriptions of the peritoneum as far as the relations of the omentum and transverse colon are concerned. The old account, that which makes the transverse colon to be between the two ascending layers of the great omentum, is first given. Afterwards the new account is repeated ; this says that the colon is not between the layers of the great omentum, but only adherent to them. The development of the colon is next mentioned, and Haller’s theory, that the colon and omentum become adherent, is discussed. Reasons are given to show that the old account of the peritoneum is the true one, and that, therefore, Haller’s theory is unacceptable. After speaking of the development of the omentum and its relation to the transverse colon, the changes which the author believes to occur are described. Instead of adhesion taking place between the omentum and colon, it is shown that the peritoneal fossa, which a t early periods exists between them, gradually disappears, owing to an unfolding or drawing out of the peritoneum at that point. It is further shown that when this has taken place the transverse colon comes to be between the two ascending layers of the great omentum. A brief description of the anatomical preparations which accompany the paper is also given.