Malus by the larvae of a large number of Lepidoptera species; see list of Lepidoptera that feed on "Malus". The fruit is a globose pome, varying in size from diameter in most of the wild species, to in "M. sylvestris sieversii", in "M. domestica", and even larger in certain cultivated orchard apples. The centre of the fruit contains five carpels arranged star-like, each containing one or two seeds. For the "Malus pumila" cultivars, the culinary, and eating apples, see Apple. Crabapples are popular as compact ornamental trees, providing blossom in Spring and colourful fruit in Autumn. The fruits often persist throughout
Étienne-Louis Malus Étienne-Louis Malus Étienne-Louis Malus (; ; 23 July 1775 – 24 February 1812) was a French officer, engineer, physicist, and mathematician. Malus was born in Paris, France. He participated in Napoleon's expedition into Egypt (1798 to 1801) and was a member of the mathematics section of the Institut d'Égypte. Malus became a member of the Académie des Sciences in 1810. In 1810 the Royal Society of London awarded him the Rumford Medal. His mathematical work was almost entirely concerned with the study of light. He studied geometric systems called "ray systems", closely connected to Julius Plücker's "line geometry". He conducted