TRANSVERSE SECTIONS 



US 



Transverse Section through the Stomach (Fig. 106).— The section passes through 

 the upper limb buds and just caudal to the point at which the descending aorta unite to form 

 the median dorsal aorta. As the liver develops in early stages, it comes into relation with the 

 plica vcikc cavec along the dorsal body wall to the right side of the dorsal mesogastrium. The 



Myotome 



Descending aorta 

 Esophagus 



Sinus venosus 



Valve of 

 Sinus Venosus 



n. atrium 



Afno- ventricular 

 opening 



Inter ventricular 

 Septum 



n.Ventricle 

 Somatopleure 



Spinal cord 



L Common 

 cardinal Vein 



Jnfervenlric- 

 ular foramen 



Pericardial 

 cavity 



Fig. 104. — Transverse section through the four chambers of the heart of a 6 mm. pig embryo. 



_ Spinal 'cord 



Spinal ganglion 

 Spinal nerve 



Descending aorta 



Pleuro-peri- 



toneal cavity 



ft. lung hud 



Rvitelline vein 

 Septum fransversum 



Pericardial 

 Cavity 



ff.ventric/e 



Upper limb bud 



Post, cardinal 

 Vein 



Esophagus 



Dorsal 

 lobe liver 



Lesser sac 



L. vitelline 

 Vein 



L.venTricle 



X 26.5. 



Fig. 105. —Transverse section through the right lung bud and septum transversum of a 6 mm. pig 



embryo. X 26.5. 



