http://www.bartleby.com/107/28.html
And this: http://www.louisville.edu/~pjdibl01/uni ... uote]There are normally 24 ribs, with 12 on each (left and right) side. They are paired, flat bones that articulate with the thoracic vertebrae on the proximal end and, on the distal end, the first seven articulate with the sternum, via cartilage. The eighth, ninth and tenth ribs articulate with cartilage on the distal end, which attaches to the cartilage of the first seven ribs. The eleventh and twelfth ribs end in cartilage and do not articulate distally with the other ribs or cartilage.[/quote]The ribs are elastic arches of bone, which form a large part of the thoracic skeleton. They are twelve in number on either side; but this number may be increased by the development of a cervical or lumbar rib, or may be diminished to eleven.
Darnit, i though i was a special case for a while there. Oh well.