Fig. 26-8. Scheme of mesenteric attachments and of the rotation of the gut. A, Early fetal period. Note that the colon crosses ventral to the duodenum. The small intestine is being reduced, that is, withdrawn into the abdominal cavity through the umbilical ring. B, Slightly later in the fetal period. The intestine is completely reduced. The axis of rotation of the gut is the superior mesenteric artery. C, The fixation of mesenteries in the adult. Note that every second part of the alimentary canal retains a mesentery. Click for high resolution image.