EEGIONAL ANATOMY 7 



A. THE BONES. 



The Second Phalanx, Os Coron.e, or Small Pastern 



Bone. — This belongs to the class of small bones, in that it 



possesses no medullary canal. It is situated obliquely in 



the digit, running from above downwards and from behind 



Fig. 1. 



-The Bones of the Phalanx. 



the OS coronfe ; 3, the os pedis ; 4, the navicular 



1, The OS suffraginis ; 2, 



bone, hidden l.y the wing of the os pedis, is in articulation in the position 

 indicated by tlie barbed line. 



to before, and articulating superiorly with the first phalanx 

 or OS suffraginis, and inferiorly with the third phalanx and 

 the navicular bone. 



Cubical in shape, it is flattened from before to behind, 

 and may be described as possessing six surfaces : An 



