(as they are called), some of them implying considerable organic changes; and each in its turn being favoured by Natural Selection". From 1860 to 1880 saltation had been a minority viewpoint, to the extent that Galton felt his writings were being universally ignored. By 1890 it became a widely held theory, and his views helped to launch a major controversy. Bateson's discontinuous variation, 1894 William Bateson's 1894 book Materials for the Study of Variation, Treated with Especial Regard to Discontinuity in the Origin of Species marked the arrival of mutationist thinking, before the rediscovery of Mendel's laws. He examined discontinuous variation (implying a form of saltation) where it occurred naturally, following William Keith Brooks, Galton, Thomas Henry Huxley and St. George Jackson Mivart. Early 20th century mutationism De Vries and Mendelian mutationstheorie, 1901 Hugo de Vries's careful 1901 studies of wild variants of the evening primrose Oenothera lamarckiana showed that distinct new forms could arise suddenly in nature, apparently at random, and could be propagated for many generations without dissipation or blending. He gave such changes the name "mutation". By this, de Vries meant that a new form of the plant was created in a single step (not the same as a mutation in the modern sense); no long period of natural selection was required for speciation, and nor was reproductive isolation. In the view of the historian of science Peter J. Bowler, De Vries used the term to mean The historian of science Betty Smocovitis described mutationism as: De Vries set out his position, known as Mutationstheorie (mutation theory) on the creative nature of mutation in his 1905 book Species and Varieties: their Origin by Mutation. In the view of the historian of science Edward Larson, de Vries was the person largely responsible for transforming Victorian era saltationism into early 20th century mutation theory, "and in doing so pushed Darwinism near the verge of extinction as a viable scientific theory". Johannsen's "pure line" experiments, 1903 In the early 1900s, Darwin's mechanism of natural selection was understood by believers in continuous variation, principally the biometricians Walter Weldon and Karl Pearson, to be able to work on a continuously varying characteristic, whereas de Vries argued that selection on such characteristics would be ineffective. Wilhelm Johannsen's "pure line" experiments on Phaseolus vulgaris beans appeared to refute this mechanism. Using the true-breeding Princess variety of bean, carefully inbred within weight classes, Johannsen's work