98 The Development of the Lymphatic System in Rabbits 
by the avoidance of rupture of very thin-walled vessels and by the oppor- 
tunity of seeing lymphatics too small for injection. The method has 
been employed with the following results. 
Hie. 2. Rabbit, 14 days, 10 mm., H. BE. C., Series 155, <x 13 diams: The 
lymphatic vessels are heavily shaded, as in all the following figures. The 
veins are those of the left side: An. 7., anterior tibial; C., caudal; c. D., 
“connecting branch”’; D. C., duct of Cuvier; Hz. J., external jugular; Ha. M., 
external mammary; Jn.J., internal jugular; P.C., posterior cardinal; Pr. Fi., 
primitive fibular; Pr. Ul., primitive ulnar. 
In a rabbit of 13 days, 9.5 mm., no lymphatics could be found. ‘The 
reconstruction, Fig. 1, shows the veins along which the first lymphatics are 
soon to appear. The internal jugular vein receives a great many small 
