The 1908 Christmas Seals on the Postcard are listed in the Scott catalog as WX3. These seals were issued in several variations. Type I (Small C and square frame corners), Type II (Large C and rounded frame corners) and in both a Perforated 12 and 14 version. There were also two types of gum on the reverse, (smooth or grilled). The value of this Christmas Seal depends on which of the variations are contained on the stamp. The two Christmas Seals illustrated above are both Type I with a Perforation count of 14. The value for this seal would be either $35 or $40 unused with original glue depending on whether it was the smooth or grilled gum type. 

Christmas Seals were not especially collected as a part of this postal history collection, however they were collected as collateral on used Christmas postcards with Rhode Island cancellations. Therefore a valuation of these collectables was undetermined as the Scott catalog only values them in mint condition.

Christmas Seals were first issued in Denmark in 1904. The first Christmas Seal in the United States was designed by Emily Bissell and issued in 1907 by the Delaware Chapter of the American Red Cross. The Red Cross continued to issue them until 1919. From 1920 to 1967 they were produced by the National Tuberculosis Association and in conjunction with the Respiratory Disease Association until 1972. Since 1973, the seals have been issued by the American Lung Association.

Although not an actual stamp, Christmas Seals have been used on letters and cards during the Christmas season since their inception and perhaps due to this long association with the postal system; they are listed in many of the stamp catalogs and are considered very collectable. A few of them are quite valuable with a 1913 Type 1 listing for $1000.

A postage stamp, (Scott #1823) was issued in 1980 honoring Emily Bissell.