Modes of cell reproduction. A, B, and C, stages in the reproduction of the Infusorian, Colpoda, by the breaking up of the protoplasm to form numerous cells. A, encysted stage; B, protoplasm escaping, spores partly formed; C, spores completely separated; D, budding in Chlamydomyxa, a lowly Rhizopod. b, bud; cw., cell wall; m, mother cell; n, nuclear matter; s, spores.
Thomas Walton Galloway, Zoology A Text-Book For Secondary Schools, Normal Schools and Colleges (Philadelphia: P. Plakiston's Son & Co., 1913) 21
Courtesy the private collection of Roy Winkelman