As I understand, there are three unique backs, the Series of 29, Series of 36 and the USA blank. In the Series of 36, the third line reads "Wilbur Chocolate Bars" and in the 29 Series the third line reads "Wilbur 1c Chocolate Bars". I have two examples of the Series of 29 type with the "1c" price omitted, but the space for the characters is there. Does anyone have an explanation for this?
No explanation that I know of. I only have the set of 29 and I have only had it for a few weeks so I'm no expert. It sure looks as though they simply removed the one cent from the printing plate. Do you suppose that they raised the price over the course of these cards lifespan? Do we know of a firm issue date for the series of 29? what about the series of 36?
I realize that I have not helped at all but I'm curious just as you are.