The spleen is a lymphatic organ which appears during the 5th developmental week as a focus of mesenchymal proliferation between the layers of the dorsal mesogastrium. As the stomach rotates, the left part of the dorsal mesogastrium comprises the gastrolineal and lienorenal ligaments. The mesenchymal cells differentiate into the parenchymal cells, connective tissue and the surface capsule. The spleen functions as a hematopoietic center until late fetal life.

1. Liver
2. Stomach
3. Spleen
4. Pancreas
5. Adrenal gland
6. Aorta
7. Dorsal mesogastrium
8. Omental bursa
9. Falciform ligament
10. Lesser omentum

1. Liver
2. Stomach
3. Spleen
4. Pancreas
5. Adrenal gland
6. Aorta
7. Lesser omentum
8. Lienorenal ligament
9. Gastrolienal ligament
10. Falciform ligament
11. Parietal peritoneum