The color-changing sense and "homing instinct" so-called--These faculties not instincts but true senses--The chromatic function --Tinctumutation--Chromatophores and their function--Various theories--Experiments of Paul Bert with axolotls--Semper's contention--The difference between plant coloring and animal coloring--Effects of light--Experiments with newts--Lister's observations--Pouchet's experiments--Sympathetic nerves--Author's experiments with frogs--The sense-centre of tinctumutation--Effects of atropia--Experiments with fish--With katydid--The "homing instinct" a true sense--Evidences of the sense in a water-louse--Author's experiments with snails--Location of sense-centre in snails--Evidences of the homing sense in the limpet--In beetles--In fleas--In ants--In snakes--In birds--In fish. 181 CHAPTER IX LETISIMULATION Not confined to any family, order, or species of animals--Death-feigning by rhizopods--By fresh-water annelids--By the larvæ of butterflies and beetles--By free-swimming rotifers--By snakes--By the itch insect (_Sarcoptes hominis_)--By many of the _Coleoptera_--The common "tumble bug" (_Canthon Lævis_) a gifted letisimulant--The double defence of the pentatomid, "stink-bug"--Reason coming to the aid of instinct-- Death-feigning an instinct--Feigning of death by ants--By a hound--Not instinctive in the dog and cat--The origin of this instinct--Summary. 202 CONCLUSION Instinct and reason--Specialized instincts and "intelligent accidents" --Abstraction in the dog--In the elephant--The kinship of mind in man and the lower animals shown by the phenomenon of dreaming--By the effects of drugs--The action of alcohol on rhizopods--On jelly-fish --On insects--On mammals--Animals aware of the medical qualities of certain substances--Recognition of property rights--Animals as tool users--Instinct and reason differentiated--Summary. 215 BIBLIOGRAPHY 225 INDEX 227 * * * * * DAWN OF REASON MENTAL TRAITS IN THE LOWER ANIMALS INTRODUCTION.--CONSCIOUS AND UNCONSCIOUS MIND Mind is a resultant of nerve, in the beginning of life, neuro-plasmic, action, through which and by which animal life in all its phases is consciously and unconsciously, directly and indirectly, maintained, sustained, governed, and directed. This definition of mind is widely different from the definition of those metaphysical scientists who directed psychological investigation and observation a decade ago. They held that psychology had nothing in common with physiology and morphology; that _psychos_ stood upon an independent pedestal, and was not affected by, and did not affect, any of the phenomena of life.