. The development of the chick; an introduction to embryology . region of the greatest curvature it descends directly in the middleline, then bends sharply to the left and is attached to the dorsalwall of the stomach; the accessory mesentery arises at the bend.(See Chap. XI.) The stomach does not rotate on its long axis soas to carry the attachment of the mesogastrium to the extreme 310 THE DEVELOPMENT OF THE CHICK left, as in niuninials; in the cliick the latenil bending of thestomach appears to be uncompUcated Ijv any such rotation. Thecurvature leaves a large space within it to the right co
. The development of the chick; an introduction to embryology . region of the greatest curvature it descends directly in the middleline, then bends sharply to the left and is attached to the dorsalwall of the stomach; the accessory mesentery arises at the bend.(See Chap. XI.) The stomach does not rotate on its long axis soas to carry the attachment of the mesogastrium to the extreme 310 THE DEVELOPMENT OF THE CHICK left, as in niuninials; in the cliick the latenil bending of thestomach appears to be uncompUcated Ijv any such rotation. Thecurvature leaves a large space within it to the right containingthe meatus venosus and liver, in short, the entire median massof the septum transversum. The main divisions of the intestine are marked out by theirposition, size-relations and structure before the closure of theyolk-stalk; thus on the third day the oesophagus appears as aconstricted portion immediately behind the pharynx, and thestomach as a spindle-shaped enlargement behind the oesophagus;the duodenum is indicated at the same time by the hepatic and. Fig. 179. — Viscera of a cliick embryo of 6days, seen from the right side. (AfterDuval.) All., Allantois. Au. r., Right a., Bulbus arteriosus, c. pr., Cjpcal pro-cesses. D. L., Loop of the duodenum. Giz.,Gizzard. Lg. r., Right lung. Li., , Rectum, t. R., Tubal ridge. V., Ven-tricle. W. B., Wolffian body. Y. St., Yolkstalk. X., Duodeno-jcjunal flexure. pancreatic outgrowths. The form of the intestine on the sixthday is illustrated in Figure 179. Behind the stomach, the intes-tine forms two lo()i)s descending ventrally. The first or duodenalloo]) is relatively slightly developed at this time, and forms anopen curve just beneath the right lobe of the liver. Its ascend-ing limb rises to a high dorsal position just behind the liver, and ALIMEXTARY TRACT AND ITS APPENDAGES 311 bends sharply to enter the descending Hmb of the second bend or duodeno-jejunal flexure (X, Fig. 179) is a relativelyfixed
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