690 



WOUND HEALING 



Fig. 12. The same patient three weeks following removal of the outer table of the skull 

 showing the profuse granulations which form over the inner table. 



Fig. 13. The same patient following the application of split thickness skin grafts to the 



granulating area. 



are derived from a resting or miiJtipotent cell type, the new vascular system arises 

 entirely from endothelial cells. 



Concerning the role of reticulo-endothelial cells, there is an active migration of 

 macrophages and round cells which always preceeds the formation of capillary 

 buds. These cells can be identified in vivo using a transparent chamber; and in vitro, 



