Fig. 8. Uptake of ferritin particles by an endothelial cell in a blood capillary 

 (rat heart muscle). Cf. Fig. ."). 1 = lumen of cell; v = vesiculations. The 

 small dense dots are ferritin particles, many of which can be seen inside the 



vesicles. 

 Magnification = 90,000. (Kindly loaned by S. Wissig and G. E. Palade, 



unpublished.) 



[facing page 24 



