PRINCIPLES OF VETERINARY SURGERY 



593 



modified. After the zone of hyaline cartilage the carti- 

 lag-inous cells are found in very irregular series, and the 

 arrangement in series is even much less clear in the large 

 spaces. The parent capsules do not dissolve and their cells 

 within also remain surrounded by their capsules. The struct- 

 ureless, cartilaginous substance is strewn with numerous 

 capsules containing a single cell with a more or less con- 

 densed protoplasm ; or with parent capsules containing mi- 

 nor capsules. 





Fig. 93. 

 Zone of Ossification in a Diaphyseal Cartilage Attacked with Rachitis 



(300 Diameters), 

 cc. Ordinary Cartilage Developing. The Capsules are Thickening and 

 Have Formed Cavities Containing Stars (Cartilaginous Cells that Have 

 Become Bone), co. Calcareous Infiltration of the Bone Cells of the 

 Cartilage, co. Capsules of the Cells, Invaded with Lime Commencing 

 to Mingle Together, o. Osseous Substance. 



Around the capsules may be seen undissolved granula- 

 tions of calcareous salts, and lastly, at the same point, large 

 vessels are found in the cartilage. This cartilaginous tissue 

 sends irregular prolongations into the diaphysis, which may 

 even become isolated by forming cartilaginous zones in the 

 midst of the bone. In the medullary cavities, which form 

 a continuation of the rachitic cartilaginous tissue or which 

 are, as it often happens, contained in the midst of this tis- 



