[rustbucket]

Ah, found it. The 34th parallel was claimed as the boundary by Lt. Col. John Baylor, commander of the Second Texas Mounted Rifles, Confederate Army, in the Territory on August 1, 1861.

I, John R. Baylor, lieutenant-colonel, commanding the Confederate Army in the Territory of Arizona, hereby take possession of said Territory in the name and behalf of the Confederate States of America.

For all purposes herein specified, and until otherwise decreed or provided, the Territory of Arizona shall comprise all that portion of New Mexico lying south of the thirty-fourth parallel of north latitude."

This comes from the Sherod Hunter SCV site, History of the Arizona Territory

[capitan_refugio]

Good work. It's fun when you run across something like that.