This is the oldest cultivar and common ancestor of all grapefruit. It was the first to be introduced to Florida, where it is still grown. The variety was described around 1892 and propagated by A. L. Duncan.
The plant is vigorous, highly productive, and fairly cold hardy. It becomes fully productive at 5–6 years old. The fruit is large and oblate or obovate, with smooth, medium-thick rind. The juicy flesh has an excellent flavour. The fruit generally ripens in February. Due to the high number of seeds (30–50), it is used for juice.