Lysichiton americanus

A very upmarket name but my RHS encyclopeadia informs me that it's common name is: yellow skunk cabbage, which sounds a lot more downmarket. It thrives in boggy ground apparently and in spring before large green leaves appear produces thise showy yellow spathes.
I found it during a walk in Dawyck Botanical Garden today on a wonderfully sunny day. More pictures of my visit are on my blog.