Sebago Skiff
Benson turned out to be exactly correct, as usual. The boat is a 16-foot smooth lapstrake Sebago skiff built in East Sebago, Maine, by Curtis Sanborn and Carlton Martin somewhere between 1890 and 1920. It's related to a lot of Northeastern skiffs generally named after bodies of water such as the St. Lawrence skiff, Chesapeake Bay skiff, Lake George skiff, Rangeley Lake skiff, and also to the double-end canoes made by Old Town and White. Sebago is a big lake in Maine.
Kevin Martin restored the skiff--it didn't need much work--and last weekend I launched it on the Connecticut River. It's a lovely boat on the water, stable, and takes waves well. I'll attach a picture of how it looked before Kevin worked on it, and a couple shots from its first day back on the water.
Norm