240 



CONNECTIVE TISSUE. 



deposition of lime-salts starts from the center of each head, inde- 

 pendently of the calcified shaft. The frame of calcined basis- 

 substance in this situation is of a roundish form, agreeing with 

 the general shape of the cartilaginous head. In some cartilagi- 



nous heads of long bones, the calcification occurs at a very early 

 period, f. i., in the vertebral ends of ribs ; while in short bones 

 the calcification, always starting from the center of the pre- 



