The idea of dragon bones might first conjure up images of Targaryen throne room decorations from Game of Thrones, but they are a necessary step in the creation of a Middle Earthian dragon.  Who knew that the understructure of Smaug the Magnificent consisted of abandoned canopy poles, yard irrigation hose and 2X4s?  Smaug just needs some skin, teeth, eyes and scales to become the fierce occupier of Erebor we all know and love.