Hi CK,
Old Town 121208 is a 13' CS (common sense or middle) grade 50-pound model canoe that was completed April-July of 1937, with open spruce gunwales, oak decks, thwarts, and seats, and a keel. Originally dark green in color. The canoe was shipped to Ware, MA, on August 12, 1937.
I'll attach information about this canoe from the 1937 catalog-- no mention is made of the thwart being removable, but my guess is that this was done so more stuff could be loaded into the canoe. These images, posted below, are from "The Complete Old Town Canoe Company Catalog Collection, 1901- 1993", available on CD from
http://www.wcha.org/catalog/ and
http://www.dragonflycanoe.com/cdrom.htm on the web.
The scan of your build record record is attached below-- click on it to get a larger image.
This scan and several hundred thousand others were created with substantial grants from the Wooden Canoe Heritage Association (WCHA) and others. A description of the project to preserve these records is available at
http://www.wcha.org/ot_records/ if you want more details. I hope that anyone reading this will join or renew membership to the WCHA so that services like this can continue. See
http://www.wcha.org/wcha/ to learn more about the WCHA and
http://www.wcha.org/join.php to renew.
It is also possible that you could have another number or manufacturer if this description don't match your canoe. Feel free to reply here if you have any other questions.
Kathy