Thread:Patrick.vtap/@comment-26453572-20160628155909/@comment-26453572-20160628180021

Notice how the wings are arms. The "spines" inside of the wing are just fingers, and the wing membrane is just webbing between said fingers. That "extra" finger on top of the wing is their version of a thumb. Considering that dragons have four legs and wings, they pretty much have four legs and two arms.