This pattern resembles one shown in "Great American Glass from the Roaring 20s and the Depression Era" by Measell and Wiggins (book 1), page 106 as Lancaster #75. It is also shown in an advertisement in "Great American Glass from the Roaring 20s and the Depression Era, Book 2" by Measell and Wiggins. It is not, however, shown in the Lancaster book by John P. Zastowney.
Under magnification, there is faint vertical paneling on the inside of the sugar. To be Lancaster # 75, these panels should rise all the way to the rim. They do not. Therefore, pending further research, this set is considered an Unknown.
