
These and some subsequent issues have a "Cross in Oval" (Wmk 182) seen on the back of the stamp. The watermark is not a true watermark, as it was impressed after the paper was produced, but before gum was applied.
BTW, there are two major types of watermark: Type 1- width under 9 mm, and Type 2- width under 8 1/2 mm.
http://bigblue1840-1940.blogspot.co...zerland.html