'I'lii' Origin and Development oj the Lymphatic System. 



Fig. 8. — Injection of the right jugular lymph sac in foetal pig measuring 

 3.5 cm. Magnified about 10 times. After A. H. Clark ( 24 I : this specimen 

 was shown as fig. :'. in 130; it has since been cleared by the Spalteholz 

 method so that it shows the relation of the superficial lymph vessels to the 

 jugular sac. It shows a complete injection of the suprascapular and oc- 

 cipital plexuses, but an incomplete injection of the superficial cervical 

 plexus. S. s. = the stalk of the sac showing faintly through the shoulder; 

 V. 1. f. = vena linguofacialis. 



