Some time ago, comments to my post about the Oceanic "five-part canoe" led to further posts about the Bronze Age boat found in Denmark known as the Hjortspring or Als boat. Basing my posts mainly on Bjorn Landstrom's illustration and description, I stated that Hjortspring was not much like the 5-part dugout of Oceania. Some months later, reader Edwin added a comment to the contrary to my original post about the Oceanic canoe.
Having subsequently read Basil Greenhill's Archaeology of the Boat (discussed here), I found a good detailed illustration of Hjortspring's bow (shown above) which validates Edwin's comments. The bottom is indeed dugout-based, and the ends (labeled "stem piece" here) are quite like the crotch-pieces of Oceanic canoes in function (if you discount the unusual horn-like structures outboard of the crotches, that may be related to an earlier skin-boat ancestor). Where they differ is in the planks. In the Oceanic canoe, the first set of strakes equals the height of the crotches, and occasionally a wash-strake is added to raise the sides. In Hjortspring, the first and second planks together equal the height of the crotch-piece. As is often the case in the five-part canoe, Hjortspring was sewn together.