ORIGIN OF VASCULAR TISSUES 



FliANKLlN P. KEAGAN 



PLATE 7 











' Aort. 



31 



Vis.mes. Ent. p^^^^^ 





/•. 



x»f 









34 



'f 



Pv.inch. pg 



Endc, 



35 



X'2> -'*'- 



16*' *' Ai 



-■<^":v 





36 



145 



THE AMERICAN JOURNAL OF ANATOMY, VOL. 21, NO. 1 



