Fretsaw
From DT Online
Fretsaws are a type of framesaw used in fine work, to cut intricate shapes out of veneer and thin Ply to create marquetry pictures for example. A Scroll saw is a powered version of a Fretsaw.
Very fine teeth blades are clamped and tensioned within a frame. They face towards the handle because they are used by pulling vertically down against a V Board as shown.
Note: To cut internal shapes, small holes are first drilled in the material through which to thread the blade