What Happened To Scott # 451 ?

Hi,
I'm currently putting my classic US stamp collection on spreadsheets. My main reason is to not buy duplicates, and to target special stamps I want to be on the lookout for.......

Anyway, in listing the Scott numbers, I find - or rather don't find - any record of a number 451. What happened here?

Thanks,
Mobilman44

Scott changed their numbering system about 1918?. I know the old system was used in my 1916 cat and the new system in 1921. The 1921 did not list 449, 450 or 451 and these were probably used as place holders. I would think that it was probably held for a possible 3 cent endwise watermarked coil.

At one time, it was believed the bureau made a perf-10 type-II horizontal coil on watermarked paper. Scotts had listed this with a high price - even higher than the current SC449. None were ever found and subsequent research pretty much proved they do not exist.

While the above answers may be true, if you go way back to 1916, the Scott Catalog for that period is available on-line. The numbering system was completely different back then, as it included Back of the Book stamps in the general numbering system.

In 1916, Scott #451 was actually listed as the 2-cent Parcel Post Stamp that we know today as Scott #Q2, as evidenced here:



According to this Linn's Stamp News article, it wasn't until 1940 that the present Scott numbering system re-designated many "special use" stamps with a prefix letter and relegated them to "Back of the Book" status:

http://www.linns.com/howto/refreshe...rcourse.aspx

Here is the 1921 Scott listing