How many faces, edges does a triangular base have?

A square pyramid has 4 trianglular faces and a square base. Each triangular face has 3 sides, which are edges of the pyramid. So should there be 4 times 3 or 12 lateral edges, plus the 4 on the square base, which would be 16 edges in all. But I only counted 8 edges. What is the matter with this picture?