:t"IGURE 171 



171 Reconstruction of left vascular complex of lower cervical and upper thoracic 

 regions in a 15.5 mm. cat embryo, (series 143, slides VIII, IX, X, and XI), X 225. 

 View from behind and from right side. 



1 Sympathetic nerve. 



.'V Right azygos arch, 



."i Right j)rt'cava. 



6 Left precava. 



6' Left azygos vein, thoratnc portion. 



7 Aorta. 



12 Jugular lymph sac, thoracic duct approach. 



13 Jugular lymph sac, jugular approach. 

 17 Prevertebral venous plexus. 



19 Suprathymic venous plexus. 



20 Subtliymi(; venous plexus. 



21 Thymus. 



22 Vagus. 



23 Left carotid artery-. 

 23' Right carotid artery. 



24 Thyrocervical artery. 



29 Jugulo-subclavian truidv. 



35 Thoracic duel, i)r('azygos scgnictit . 



36 Thoracic duct, azygos segment. 



40 Innominate vein. 



41 Vertebral artery. 



42 Vertebral vein. 



45 Innominalc artery. 



54 Fiftli spinal nerve. 



55 Sixth, seventh and ciglitii spinal nerve 

 57 Right subclavian artery. 



