PLATE 16 



EXPLANATION OF FIGURE 



27 Drawn from a reconstruction of a chick embryo of days and 14 hours 

 (series no. 320). Ventral view. 



1, aorta 



^, dorsal aortic roots 



3, aortic arch VI 



3a, puhnonary artery 



4, aortic arch IV 



5, celiac artery 

 7, carotid artery 



9, superior mesenteric artery 



10, p ecardinal (juguhir) vciii 

 //, subchivian vein 



12, duct of Cuvier 

 15, juguhir lymph sac 

 15(1, thoracic duct 'approach' of jugular 

 lymph sac 



16, groups of developing blood cells 



17, thoracic duct, ventral plexus (honio- 

 logue of azygos segment. 



17a, thoracic duct (homologue of pre- 

 azygos segment. 



18, lymphatics along aortic arches 



19, lymphatics dorsal to aortic roots 

 and arches 



£1, mesenteric lymphatics 

 ^^, lymphatics associated with esoph- 

 agus 



194 



