Greatly enlarged. One-piece model shows the most significant features of a human male embryo of about 28 days. The left half is presented in partial median section to expose the position of various structures. Specific features include the embryonic heart loop in the pericardial cavity; primary formation of the intestinal tube with pharyngeal pouches in the foregut region; early development of the liver; umbilical loop; hindgut with allantois; and beginning of the umbilicus. Also clearly visible is the early formation of the neural medullary tube. Mounted on a base. Size (without base), 17 × 18 × 18 cm.