DEVELOPMENT OF BONE. 



Pig. 2.' 



V* " 



y 





augmented with proximity to the ossifying point, and each cell in 

 place of producing two, gives birth to four, five, or six young cells, 



Fig. 3.t 



C? ^fj* 



which rapidly destroy the parent membrane and attain a greater size 

 (ysW f an inch) than the parent cell, each cell being, as in the pre- 

 vious case, separated to a slight extent from its neighbour by inter- 



* Figures illustrative of the development of bone ; they are magnified 155 

 times, and drawn with the camera lucida. A. A portion of cartilage, the farthest 

 removed from the seat of ossification, showing simple nucleated cells, having 

 an ordinary size of jjcTTTfir of an inch, long diameter. B. The same cartilage 

 nearer to the seat of ossification ; each simple cell has produced two, which are 

 a little larger than the cells in figure A. 



t The same cartilage, still nearer the seat of ossification ; each single cell of 

 B has given birth to four, five, or six cells, which form clusters. These clusters 

 become larger towards the right of the figure, and their cells more numerous 

 and larger, T3TTo of an inch, long diameter. 



