FIGURES 83 AND 84 



83 Transverse section of left lower cervical region in a 17 mm. cat embryo 

 (series 142, slide X, section 13), X 225. 



84 Same, section 16. 



1 Sympathetic nerve. 



12 Jugular lymph sac, thoracic duct approach. 



13 Jugular lymph sac, jugular approach. 



14 Jugular lymph sac, subclavian approach. 



21 Thymus. 



22 Vagus. 



24 Thyrocervical artery. 



25 Internal jugular vein. 



29 Jugulo-subclavian trunk. 



