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Elementary Biology. 



modification. The cells are repeatedly branched, and lie 

 in spaces (lacunae), which are moulded to the form of the 

 contained cell. The branched processes of the cells lie in 

 delicate canals (canaliculi), and these again communicate 

 with the canaliculi of neighbouring lacunae. Moreover the 



FIG. 159. HYALINE CAHTTLAGE. (Quain.) 



a, group of two cells ; b, group of four cells ; ft, protoplasm of cell, with 

 fat granules, ; , nucleus. 



lacunae themselves are arranged in circles round larger 

 spaces (Haversian canals) which contain one or more blood- 

 vessels. The Haversian canals anastomose and form a com- 

 plete network in the bone and act as the channels by which 

 nutrient blood-vessels pass to every part of the bone. 



