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e representatives of animals； others of plants； but in all cases they are to be regarded as intermediate stages in the transition of an animal or plant ancestor into a human individual who bore its name as that of his or her totem。〃 （Baldwin Spencer and F。J。 Gillen； 〃Native Tribes of Central Australia〃； pages 391 sq。） In a sense these speculations of the Arunta on their own origin may be said to combine the theory of creation with the theory of evolution； for while they represent men as developed out of much simpler forms of life； they at the same time assume that this development was effected by the agency of two powerful beings； whom so far we may call creators。 It is well known that at a far higher stage of culture a crude form of the evolutionary hypothesis was propounded by the Greek philosopher Empedocles。 He imagined that shapeless lumps of earth and water； thrown up by the subterranean fires； developed into monstrous animals； bulls with the heads of men； men with the heads of bulls； and so forth； till at last； these hybrid forms being gradually eliminated； the various existing species of animals and men were evolved。 （E。 Zeller； 〃Die Philosophie der Griechen〃； I。4 （Leipsic； 1876）； pages 718 sq。； H。 Ritter et L。 Preller； 〃Historia Philosophiae Graecae et Romanae ex fontium locis contexta〃5； pages 102 sq。 H。 Diels； 〃Die Fragmente der Vorsokratiker〃2； I。 （Berlin； 1906）； pages 190 sqq。 Compare Lucretius 〃De rerum natura〃； V。 837 sqq。） The theory of the civilised Greek of Sicily may be set beside the similar theory of the savage Arunta of Central Australia。 Both represent gropings of the human mind in the dark abyss of the past； both were in a measure grotesque anticipations of the modern theory of evolution。
In this essay I have made no attempt to illustrate all the many various and divergent views which primitive man has taken of his own origin。 I have confined myself to collecting examples of two radically different views； which may be distinguished as the theory of creation and the theory of evolution。 According to the one； man was fashioned in his existing shape by a god or other powerful being； according to the other he was evolved by a natural process out of lower forms of animal life。 Roughly speaking； these two theories still divide the civilised world between them。 The partisans of each can appeal in support of their view to a large consensus of opinion； and if truth were to be decided by weighing the one consensus against the other； with 〃Genesis〃 in the one scale and 〃The Origin of Species〃 in the other； it might perhaps be found； when the scales were finally trimmed； that the balance hung very even between creation and evolution。
X。 THE INFLUENCE OF DARWIN ON THE STUDY OF ANIMAL EMBRYOLOGY。
By A。 SEDGWICK； M。A。； F。R。S。 Professor of Zoology and Comparative Anatomy in the University of Cambridge。
The publication of 〃The Origin of Species〃 ushered in a new era in the study of Embryology。 Whereas； before the year 1859 the facts of anatomy and development were loosely held together by the theory of types； which owed its origin to the great anatomists of the preceding generation； to Cuvier； L。 Agassiz； J。 Muller； and R。 Owen； they were now combined together into one organic whole by the theory of descent and by the hypothesis of recapitulation which was deduced from that theory。 The view （First clearly enunciated by Fritz Muller in his well…known work； 〃Fur Darwin〃； Leipzig； 1864； （English Edition； 〃Facts for Darwin〃； 1869）。） that a knowledge of embryonic and larval histories would lay bare the secrets of race…history and enable the course of evolution to be traced； and so lead to the discovery of the natural system of classification； gave a powerful stimulus to morphological study in general and to embryological investigation in particular。 In Darwin's words： 〃Embryology rises greatly in interest； when we look at the embryo as a picture； more or less obscured； of the progenitor； either in its adult or larval state； of all the members of the same great class。〃 （〃Origin〃 （6th edition）； page 396。） In the period under consideration the output of embryological work has been enormous。 No group of the animal kingdom has escaped exhaustive examination and no effort has been spared to obtain the embryos of isolated and out of the way forms； the development of which might have an important bearing upon questions of phylogeny and classification。 Marine zoological stations have been established； expeditions have been sent to distant countries； and the methods of investigation have been greatly improved。 The result of this activity has been that the main features of the developmental history of all the most important animals are now known and the curiosity as to developmental processes； so greatly excited by the promulgation of the Darwinian theory； has to a considerable extent been satisfied。
To what extent have the results of this vast activity fulfilled the expectations of the workers who have achieved them？ The Darwin centenary is a fitting moment at which to take stock of our position。 In this inquiry we shall leave out of consideration the immense and intensely interesting additions to our knowledge of Natural History。 These may be said to constitute a capital fund upon which philosophers； poets and men of science will draw for many generations。 The interest of Natural History existed long before Darwinian evolution was thought of and will endure without any reference to philosophic speculations。 She is a mistress in whose face are beauties and in whose arms are delights elsewhere unattainable。 She is and always has been pursued for her own sake without any reference to philosophy； science； or utility。
Darwin's own views of the bearing of the facts of embryology upon questions of wide scientific interest are perfectly clear。 He writes （〃Origin〃 （6th edition）； page 395。）：
〃On the other hand it is highly probable that with many animals the embryonic or larval stages show us； more or less completely； the condition of the progenitor of the whole group in its adult state。 In the great class of the Crustacea； forms wonderfully distinct from each other； namely； suctorial parasites； cirripedes； entomostraca； and even the malacostraca； appear at first as larvae under the nauplius…form； and as these larvae live and feed in the open sea； and are not adapted for any peculiar habits of life； and from other reasons assigned by Fritz Muller； it is probable that at some very remote period an independent adult animal； resembling the Nauplius； existed； and subsequently produced； along several divergent lines of descent； the above…named great Crustacean groups。 So again it is probable； from what we know of the embryos of mammals； birds； fishes； and reptiles； that these animals are the modified descendants of some ancient progenitor； which was furnished in its adult state with branchiae； a swim… bladder； four fin…like limbs； and a long tail； all fitted for an aquatic life。
〃As all the organic beings； extinct and recent； which have ever lived； can be arranged within a few great classes； and as all within each class have； according to our theory； been connected together by fine gradations； t