120 THE CONNECTIVE TISSUES, BY A. ROLLETT. 



completely surround the bone.* The spaces which remain 

 between the systems concentric to the Haversian canals in the 

 interior of the bone, and which present areas with three, four, 

 or more angles, with incurved sides, are occupied by an interla- 

 mellar mass presenting a similar lamination. The interlamel- 

 lar systems also, for the most part, run parallel to the surface 

 of the bone ; but it may also occur that they run parallel 

 to the two opposite boundaries of the areas, and stand 

 perpendicularly to others ; or there may occur in the areas 

 themselves, again, vertices of the systems of rings, which cut 

 the direction of the closed systems at various angles, as shown 

 in fig. 10. 



But we frequently also meet with concentrically arranged 

 systems pf the first order, which have become flattened by 



Fig. 10. 



Fig. 10. Transverse section of human femur, deprived_of mineral 

 matter by hydrochloric acid. 



mutual pressure, and are not separated by any interlamellar 

 substance. The latter seldom occurs in the tubular bones of 

 man, the former commonly occurs in animals. 



Freyf calls the connective systems of the first order special 



* Tomes andDe Morgan, Philosophical Transactions, 1853, Vol. i., p. 109. 

 t Histoloyie and Histochemie, 1867, p. 280. 



