 The hurried preparation and publication of the Origin between the summer of 1858 and November of 1859 was prompted by the receipt on June 18 of 1858 of a letter from Alfred Russel Wallace that outlined his remarkably similar views on the possibility of continuous species change under the action of a selection upon natural variation. This event had important implications for the subsequent form of Darwin’s published argument. Rapidly condensing the detailed arguments of the “Natural Selection” manuscript into shorter chapters, Darwin also universalized several claims that he had only developed with reference to specific groups of organisms, or which he had applied only to more limited situations in the manuscript. This resulted in a presentation of his theory at the level of broad generalization. The absence of tables of data, detailed footnotes, and references to the secondary literature in the published version also resulted in predictable criticisms which will be discussed below in  Section 3.