FIGURES 57 AND 58 



57 Transverse section through left lower cervical region of a 14 mm. cat embryo 

 (series 122, slide IX, section 21) , X 150. 



58 Same, section 28. 



1 Sympathetic nerve. 



8 Oesophagus. 



9 Trachea. 



12 Jugular lymph sac, thoracic duct approach. 



13 Jugular lymph sac, jugular approach. 



14 Jugular lymph sac, subclavian approach. 

 16 Dorso-medial somatic venous tributaries. 



21 Thymus. 



22 Vagus. 



23 Left carotid artery. 



24 Thyrocervical artery. 



25 Internal jugular vein. 



26 Common jugular vein. 

 29 Jugulo-subclavian trunk. 



