894- 



URIST, MACDONALD, MOSS, AND SKOOG 



Fig. 5A. Fluorophotomicrograph showing triple labeling of cortical bone in 

 Case No. 7. The space between the two outer rings reflects the amount of bone 

 deposited during a 15-day control period, and the space between the middle 

 and inner ring indicates the amount deposited in a 30-day period on treatment 

 with proline. With due allowance for the well known fact that the bone de- 

 position rate is high at the beginning and low at the end of the period of forma- 

 tion of a new osteon, the longer interval and wider space indicate that the treat- 

 ment did not increase the mean osteon formation time for the bone in the 

 upper end of the tibia. ( X approx. 450. ) 



bone. In high-power magnification, however, some parts of the 

 skeleton presented an abnormal change in that they had large areas 

 in which the lacunae had lost their osteocytes. The cell-free areas 

 were frequently in the outer layers of the osteons and in the inter- 

 stitial lamellae of cortical bone. The matrix also stained irregularly 

 basophilic and metachromatic rather than as a homogeneous eosino- 

 philic structure. Occasionally, it was possible to see strips of tissue 

 in which the collagen fiber bundles accepted the Wilder stain ir- 

 regularly. In some areas of the surface compacta, as, for example, in 

 the neck of the femur and the anterior cortex of the vertebral bodies 



