_Contrast between organic and human evolution_--(1) The meaning of term _fittest_ in each--(2) Destiny of the weak and helpless in each--(3) The nature of evolutionary transformation in each--(4) The law of strait and narrow way applied in each--(5) Human evolution is a different kind and on a higher plane 88 _Application to some questions of the day._ I. Neo-Darwinists, their position explained--Reasons for dissenting--(_a_) Lamarckian factors preceded all others-- (_b_) Though now subordinate, they still underlie and condition all other factors--(_c_) Shown by comparison of phylogeny with ontogeny 92 II. Human progress not identical with organic evolution--Mistake of the materialists--But neither is it wholly different, as some suppose 96 III. Neo-Darwinism is fatal to hopes of human progress--Reason may use freely Lamarckian factors, but can not use natural selection in the same way as Nature does 97 CHAPTER IV. SPECIAL PROOFS FROM THE GENERAL LAWS OF ANIMAL STRUCTURE, OR COMPARISON IN THE TAXONOMIC SERIES. _General Principles._ _Analogy and homology_--Defined and illustrated by examples-- Wings and limbs--Lungs, gradual formation of, traced in the Taxonomic series--Traced in the Ontogenic series--Examples of homology in plants: tuber, cactus-leaf, acacia-leaf-- Definitions repeated and further explained--Common origin is the only explanation of homology 99 _Primary divisions of the animal kingdom_--True ground of such divisions is ability to trace homology--We take examples only from vertebrata and articulata--Compare to styles of architecture--To machines--To branching stem 107 CHAPTER V. PROOFS FROM HOMOLOGIES OF THE VERTEBRATE SKELETON. _Common general plan_--In several respects--Strongly suggestive of common origin--Details of structure demonstrative of the same 111 _Special homology of vertebrate limbs_ 113 _Fore-limbs_--Comparison of fore-limbs of mammals, birds, reptiles, and fishes, part for part--Gradual changes in collar-bone and coracoid--In position of elbow--In bones of forearm--In position of wrist--In the tread--The term manus--Number of toes--Modifications for flight in various animals--For swimming in whales and fishes 113 _Hind-limbs_--Comparison of hind-limbs of several mammals-- Position of knee--Of heel--Plantigrade and digitigrade --Degrees of the latter--Number of toes--General law in regard to number of similar parts--Order of toe-dropping in artiodactyles--In perissodactyles 121