This is a variation I had not seen before for Thompson, with the groove in the decks, but then again, we do not see many out here in the Pacific Northwest. These are from a 1938-39 Thompson Indian.
Dan's canoe ID website shows three different Thompson deck styles-- www.dragonflycanoe.com/id/ ; click on "Thompson" on the left. One deck looks Old Townish, one looks Penn Yanish, and one looks RacineWisish... so, folks could be confused. No telling what will confuse people though--- there's a museum in Hessel with a Thompson which has the Old Townish deck, which is correctly identified as a Thompson.... and a Morris with a heart deck, identified as an Old Town.
The decks I posted were different than on Dan's site, so I thought they might be unusual because of the slot routed in the open ends, but I guess not. Most of the Thompsons I have seen have these type decks.