PLATE 10 



EXPLANATION OF FIGURE 



11 A, B, and C. Three serial sections showing the manner in which the left 

 jugulo-sub-clavian tap of the lymph sac is made in a 23 mm. Tragulus embryo. 

 Collection No. 228. X 100. 26a, dorsal descending process of the lymph sac 

 (thoracic duct approach) ; 27, ventral descending process of the lymph sac (broncho- 

 mediastina approach); 52, jugulo-sub-clavian approach; 53, confluence of the 

 jugular veins; 54, thymus; 55, thyro-cervical artery; 56, sub-clavian vein; 63, 

 ventral prolongation of the jugulo-sub-clavian approach. The relations of the 

 structure marked 52 in the three figures indicate the manner in which the second- 

 ary connection between the lymph sac and the venous system is made. 



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