From the Unconscious to the Conscious 



that the theory of mutations is strikingly confirmed. 

 By its light, and with closer study, truths which have 

 been ignored or unconsciously slurred over become 

 immediately obvious. 



These truths had, however, been already stated by 

 great naturalists such as Geoffroy Saint-Hilaire ; but 

 they made no way, and the thesis of slow transformations 

 found no one to contradict it until the work of De Vries 

 appeared. 



Starting from his theory of mutations, Cope resumed 

 the study of fossil forms, more especially of the 

 batrachians and mammals of America, and he found 

 no difficulty in demonstrating the probability of their 

 progressive variation by abrupt mutations. 



It is, moreover, easy, on the data of the palaeonto- 

 logical records which are ' the archives of creation,' to 

 verify that the appearance of most of the main species, 

 always seems to be abrupt. 



Batrachians, reptiles, birds, and mammals suddenly 

 appear in the geologic strata. Once there, they seem 

 very rapidly to acquire the characteristics which they will 

 subsequently retain without any essential modification 

 as long as the species remains in existence. 



No doubt, palaeontology presents transitional forms. 

 But these are rare, and (a more serious matter) they 

 seem to be intermediary rather than transitional. 



For example, let us take the archeopteryx, the most 

 remarkable of these intermediate species. We see a 

 bird-reptile, having affinities with each. But its species 

 is determinate and clearly specialised. The archeopteryx 

 has the constitution of the reptile, but it has also well- 

 developed wings, capable of flight, bird's wings. 



A reptile with embryonic wings, or wings indicated 

 at the beginning of their development, has never been 

 found. 



What is true for the archeopteryx is equally true for 

 all known intermediate forms; they are all well marked, 



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