BONE. 



77 



are found in the outer ground lamellae and in the true inter- 

 stitial lamellae i. e., in all lamellae which are formed from the 



FIG. 41. 



!- r :'-- r; ^~- i 



FIG. 42. 



FIGS. 41, 42. Ground cross-section through the diaphysis of the human ulna viewed with 



polarized light. X 170. 



The entire Haversian lamellar system, together with the neighboring interstitial and 

 Haversian lamellae, is shown. In the centre is the Haversian canal. Around this are 

 lamellae which contain bone spaces. Between the adjacent systems are to be seen cement 

 lines. The dark diagonal lines at the lower right side of Fig. 41 represent Sharpey's fibres. 



Fig. 41, with uncrossed ; Fig. 42, with crossed Nicol's prisms. 



The dark cross in Fig. 42 is an appearance caused by the polarization. 



periosteum. We find them also in large quantities in the 

 lamellae containing coarse fibres, spoken of above. 



The uncalcified Sharpey's fibres are destroyed in macerating 

 fluids, and also in dried specimens. From the periosteum there 



