524 



J. T. IRVING AND C. S. HANDEL^NIAN 



III _ _«^.^ i m oi ^ -^ 



Fig. 7. Decalcified implant removed after 2 weeks, showing small multi- 

 nucleated cells (arrows), possibly an early stage of giant cell development. 

 Hematoxylin and eosin. (X 350.) 



Fig. 8. Parallel section to Fig. 7 reacted for lactic dehydrogenase. Note 

 activity in the early forms of giant cells (arrows) . ( X 350.) 



Fig. 9. Part of the secondary spongiosa of the tibia of a 3-day-old rat 

 reacted for lactic dehydrogenase. Note the intense reaction in the osteoclasts. 

 (X350.) 



