Coch-y-bonddhu was a sailing dinghy and the model for Scarab; coch-y-bonddhu is the name of a fishing fly. Ransome arranged for her to be built by Crossfields, the Arnside boatbuilders who originally built Swallow. Ransome was fond of her as she was like the old "Swallow", though having a centreboard and case she was more like "Amazon/Mavis". CFT pp 93,94