Humerus bones.

All these are humerus bones.

Note the differencein sizes.

These two are Equus

As you can see therse quite a bit broken off the top, i think they belong to aurochs young and mature.
   
                                                            Sorry have just noticed this post !

The statement above was made by myself in the very early days of my work, when i new very little about mammal bones, if the post has missled anyone i appologise !  The two Humerus bones are in fact Equus not bovine.