OF THE ARTICULATIONS. 397 



urn, in passing from the one to the other bone over the inter- 

 vening cartilage, also unites these three par.ts, to which it inti- 

 mately adheres. This kind of articulation, which is very 

 solid, has no sensible motion. It favours the growth of the 

 broad bones by their edges. It is often obliterated in old age. 

 Its disunion requires efforts of the same kind and violence as 

 those which fracture the bones. 



This kind of articulation, which has received the generic 

 name of suture, presents several varieties. 



625. The true suture is that in which the edges of the ar- 

 ticulated bones present numerous and extensive eminences 

 and depressions, which receive each other. Of this kind are 

 the inter-parietal, occipito-parietal, and fronto-parietal articu- 

 lations. This suture itself presents some differences. Thus, in 

 the first, they are long tooth-like prolongations; in the second, 

 they have the form of rounded tails; in the third, they resem- 

 ble the teeth of a saw. These three varieties have received 

 the names of dentate suture, sutura dentata, serrated suture, 

 sutura serrata, and margined suture, sutura limbosa. 



The harmonic articulation, is that in which the edges of the 

 bone, which are more or less thick, present rugosities which 

 are fitted to each other; the suture by which the nasal bones 

 are joined to each other, is of this kind. 



The squamous articulation is that in which the edges of the 

 bones are sloped like a chisel, and fitted to each other like 

 the edges'of a bivalve shell. This disposition, which is very 

 decidedly marked in the junction of the parietal and temporal 

 bones, occurs combined with the suture or harmonic articula- 

 tion in many other articulations of the skull and face. In 

 many articulations, it is double and reciprocal, so that at one 

 part, a bone overlaps the other, which in another part overlaps 

 the first in its turn. Of this kind are the spheno-frontal su- 

 tures. This mortising is one of the most powerful means of 

 ensuring the solidity of the synarthrodial articulations. 



Schinclylesis is a synarthrosis which results from the recep- 

 tion of the crest or ridge of a bone into the groove of another. 

 Of this kind are the articulations of the sphenoid and ethmoid 



