Born June 6, 1868, in Jena; died Mar. 10, 1932, in Leiden. German botanist.
Hallier worked in the herbaria of Bogor on the island of Java, in Hamburg, and in Leiden. At the same time as the American botanist C. Bessey (1845-1915) he established a new phylogenetic system for angiospermous plants. (He considered the most primitive plants to be those with bisexual insect-pollinated flowers, a developed perianth, and spirally located flower parts.) This system lies at the foundation of most modern systems.