Zag-Zaw line of puzzles was first produced in 1909, most incorporate figurals or whimsies, sold in red, orange, or occasionally green boxes with labels on the side or bottom of the box, most without guide pictures. Initially cut non-interlocking but by 1930's became more so. Puzzles have a different cuts so that the same image will come in several versions which means that missing pieces can not be taken from other puzzles with the same image. The puzzle labels are often hand written and come with minor variations in titles and details. Some have a DESIGN category on the label. From my readings this refers to the style of cut, wavy lines, figurals, etc. See also Bob Armstrong's website on old jigsaw puzzles
THE LOVE LETTER, a maid dressed in blue and white sits despondently with her head on her hands against the back of a chair
about 250 pieces, wooden, figurals, complete with box, push fit style
