Collier's New Encyclopedia (1921)/Rhizopoda

RHIZOPODA, a name introduced by Dujardin for an order of infusoria, which were defined as animalcules in mutable form, moving by means of multiform exsertile processes, without vibratile cilia or other external organs. When the sub-kingdom Protozoa was formed, the name Rhizopoda was retained for the class containing individuals with the power of emitting pseudopodia, and the class was divided into five orders: Monera, Amœbea, Foraminifera, Radiolario, and Spongida. The rhizopoda are the Myxopodia of Huxley, and this latter name has been retained by Professor Lankester in his reclassification of the Protozoa.