Tread, plantigrade and digitigrade, 123. True and the good, relation of, 277. Truth tested by effect on life, 277; not compromise, 291. Types, generalized, 13. Use and disuse of organs, 73. Useless structures, how produced, 76. Variation depends on sexual reproduction, 238; caused by unfavorable conditions, 264. Varieties, artificial production of, 222, 235; artificial production of, illustrated, 224; natural and artificial, compared, 228; origin of, unexplained, 270. “Vestiges of Creation,” 34. Virtue and innocence compared, 372. Vital principle, 328. Voluntary social progress, 26. Weismann’s views, 93. Whales, rudimentary organs of, 180. THE END. Transcribers’ Notes: Punctuation, hyphenation, and spelling were made consistent when a predominant preference was found in this book; otherwise they were not changed. Simple typographical errors were corrected; occasional unbalanced quotation marks retained. Ambiguous hyphens at the ends of lines were retained. Subscripts in chemical formulas are represented here as simple numbers, such as H2O and NH3. Illustrations were printed mid-paragraph but have been moved between paragraphs, usually near to text that references them. Footnotes have been collected and repositioned just before the Index. Some in-line paragraph headings are in boldface and some are in italics; this emphasis has been retained. Index not checked for proper alphabetization or correct page references, but a reference to page 274 was a typographical error and has been changed to 174. Page 155: Text refers to _c c′_ in Figs. 38-39, but neither figure appears to contain a _c′_ label. End of the Project Gutenberg EBook of Evolution, by Joseph Le Conte