Chapter 3

_THE CO-EXISTENCE OF CLOSELY SIMILAR STRUCTURES OF DIVERSE ORIGIN._

Chances against concordant variations.--Examples of discordant ones.--Concordant variations not unlikely on a non-Darwinian evolutionary hypothesis.--Placental and implacental mammals.--Birds and reptiles.--Independent origins of similar sense organs.--The ear.--The eye.--Other coincidences.--Causes besides Natural Selection produce concordant variations in certain geographical regions.--Causes besides Natural Selection produce concordant variations in certain zoological and botanical groups.--There are homologous parts not genetically related.--Harmony in respect of the organic and inorganic worlds.--Summary and conclusion ... _Page_ 63