A form with double flowers. According to A. N. Baumann, it was noticed by him as a sport on a tree of the ordinary type growing in the garden of a Mons. Duval, near Geneva, during the years 1819 to 1822. He sent grafts to his father’s famous nursery at Bollwiller, in Alsace, whence it spread into cultivation. Its flowers last longer than those of the type, and as no nuts are formed the tree escapes the danger of injury just alluded to. For public places it is strongly recommended, and is the best of the garden varieties. It has also been called A. h. flore pleno.