248 



CONNECTIVE TISSUE. 



medullary corpuscles, while another portion remains unchanged 

 and represents the bone- corpuscles. In accordance with the 

 spindle shape of all medullary elements constituting a tract, the 

 basis-substance assumes a striated appearance. 



In growing animals, we often see rows of medullary corpuscles 

 at the borders of bone-tissue toward the medullary space, which 

 have been termed the " osteoblasts " by Gegenbaur. * That the 

 elements of these rows really produce the bone was acknowledged 



FIG. 



101. CORTICAL SUBSTANCE OF THE TIBIA OF A DOG, Six MONTHS 

 OLD. TRANSVERSE SECTION. CHROMIC ACID SPECIMEN. 



M, medullary spacefilled with medullary elements, which at the border of the bone-tissue 

 have assumed the shape of " osteoblasts." The center of the medullary space is occupied by 

 a blood-vessel. S, first trace of the formation of a Haversiau system, composed of lenticular 

 territories, which give to the circumference of the system a fluted appearance. T, globular 

 territories, evidently the starting formations of new systems of lamella}. Magnified 500 

 diameters. 



also by later observers, as Waldeyer t and A. Rollett. { A row of 

 osteoblasts is evidently the basis of a future lamella of bone. 



Before the infiltration with lime-salts takes place, a number 

 of the osteoblasts are transformed into finely granular bodies, 



* Jenaisehe Zeitschr. f. Mediz. u. Naturwissenseh. 1864 and 186(5. 

 t " Ueber den Ossificationsprocess." Archiv f. Mikroskopische Anatomic. 

 Bd. i. 1865. 



t " Handb. d. Lehre von den Geweben." Herausg. v. S. Strieker. 



