#56 Ori ifte &se'qfHw' Snfiu'h 



If it be asked, for instance, why at thfe 

 sutures thei-e'fe^k stitiilg^^r adhesion of ih^dttrk' 

 mfl'f^r Interrially ^i\d /pmostetim externally 

 than in other parts 6f the skull ? the answer iff/' 

 that these membranes with their vessels are 

 continued into the sutures, to form conjointly 

 the secretory organ, by, which the bones are 

 i^xtended. 



If it be asked, why there is a greater vascu- 

 larity or an appearance of t)lood-vessels passing 

 through the sutures ? it is perfecfly consistent 

 wnth this opinion to answer, that the increase- 

 of blood goes to this secretory organ, for the 

 purpose of the extension of the bones. 



The explanation here offered, accounts also 

 for the general obliteration of the sutures after 

 a certain period of life ; for the bones having 

 then arrived at their full size, the organ for the 

 secretion of osseous matter is no longer needed ; 

 it shrinks and is absorbed, and the bones, 

 gradually coalesce ^ by which a further ad- 



" (Internae euim iiicreinentum citius absolutum. videtur) 

 " massa ossea, augetur, iioa potest non esse, quia haec 

 *^ crispa suturce forma, qiium quidem nasci coepit, externy, 

 " in superficie tamdiu, augeatur, douce tandem ipsa ea 

 '' quam maxime impediat, quo minus cerebrum calvariam. 

 *' ulterius diducere possit, quod pubertatis tempore accidit. 

 " Rarissime hecc ossificatio ad a^tatem virilem usque de- 

 " tinetur/*— Soemmcrring do corporis lluinaui rabrica* 

 page 212. 



