40 Revieics — Prof. E. Heherfs Introduction to Geology. 



Coleoptera change but little, but the Lepidoptera pass through great 

 metamorphoses. Frogs and Toads commence life as tadpoles ; 

 whereas Salamanders differ but little at birth from their parents. 

 Many marine Gasteropoda (Prosobranchiata) undergo considerable 

 modifications, whereas young snails are snails from their first 

 appearance. If all the creatures had changed equally quickly in 

 geological time, those which have been ti-ansmitted through all the 

 past ages would all have been elevated beings at the present day. 

 There would thus have been more of the higher than of the inferior 

 animals ; more of the eaters than of the animals to be eaten. The 

 harmony of the organic world would long ago have been broken. 

 Moreover, the inequality in evolution is one of the causes of the 

 variety of aspects presented in the history of the world. 



" At all epochs, except no doubt just at the beginning, there have 

 been organisms in the first stages of their evolution, others in the 

 second, others in a third, and others in more elevated stages. It is 

 in part from these inequalities that the marvellous beauty of nature 

 in all geological periods has arisen." 



We have given this very full resume of Prof. Gaudry's views in 

 order to show that even amongst the strongest adherents of special 

 creation the doctrine of Evolution has made its way, and for the 

 obvious reason, that unlike the doctrines of Lamarck, which appealed 

 to the imagination, the Darwinian theory appeals to one's personal 

 observations, and every naturalist may test it and apply it to his own 

 special research. Not that the doctrine of Evolution is perfect and 

 complete — no one knew better than Darwin himself how many 

 tough problems remained still awaiting solution ; but it is because 

 it helps us to understand and to piece together a larger proportion 

 of the puzzle of Life on the Earth than any other theory yet 

 propounded, that geologists and naturalists of all shades of thought 

 have adopted it, some at once^ — like Sir Charles Lyell — others, like 

 Prof. Gaiidry, more slowly, but none the less surely, because they 

 have carefully tested it by actual application to their own researches. 



Prof. Hebkrt's Introduction to Geology. • , 



in. — Prof. E. Hebert's " Notions generales de Geologie." 

 18mo. pp. 114, and 54 Woodcuts. [Paris: G. Masson, 1884 

 (really Nov. 1883).] 



THIS little book is a remarkable one in many respects. It has 

 the appearance of a primer; yet it is not a primer in any sense 

 of the word. It is to a certain extent an introduction to the Science 

 of Geology, and yet it assumes in its readers a respectable amount of 

 preliminary knowledge. Again, though confessedly an introduction, 

 the work is complete in itself. Perhaps the following extracts from 

 the author's preface will best explain his object : — 



" This small methodic treatise can thus serve as an introduction 

 to thorough and detailed studies, or it may supply sufficient instruc- 

 tion to those who, otherwise employed, are yet curious to be initiated 

 into this branch of human knowledge." . ..." It is principally to 

 pupils in rhetoric and philosophy [i.e. the highest forms of the 



