TRANSLATIONS AND NOTICES 



OF 



GEOLOGICAL MEMOIRS. 



Investigations of the Laws of Development of the Organic World 

 during the period of the Formation of the Earth's Surface. By 

 Dr. H. G. Bronn. Stuttgart, 1858. 



[Untersuchungen iiber die Entwickelungs-G-esetze der organischen Welt wahrend 

 der Bilduugs-Zeit unserer Erd-Oberflache. Eine von der Franzosischen 

 Aiademie im Jahre 1857 gekronte Preisschrift. Von Dr. H. Gr. Bronn. 

 Stuttgart, 1858.] 



This remarkable work by Prof. Bronn, of Heidelberg, is the German 

 translation of the essay to which the prize was awarded by the 

 French Academy in 1856. The original subject proposed in 1850 

 and 1854 was, — 1st, "to examine the laws of the distribution of 

 fossD. organic bodies in the different sedimentary formations accord- 

 ing to the order of their superposition ; 2nd, to discuss the question 

 of their successive or simultaneous appearance or disappearance; 

 3rd, to inquire into the nature of the relations between the existing 

 state of the organic world and its anterior states." 



The work consists of two parts : the first contains the introduc- 

 tory remarks and tabular statements of the materials on which the 

 author's views are grounded, and which are chiefly taken from D'Or- 

 bigny's works and the ' Lethaea ;' viz. the different geological forma- 

 tions, the distribution of organic life, numerical proportions of fossil 

 species and genera, of fossil genera now living and those which are 

 extinct, the geological extension of the different classes of organic 

 life. 



Having thus carefully collected his materials, the author proceeds 

 in the second part to deduce the laws which have regulated the 

 phsenomena of organic life in different geological periods, and the 

 appearance and disappearance of different forms. This part consists 

 of three subdivisions : — 1st. Theoretical development of the laws of 

 the succession of organic beings. 2nd. Practical tests of the theo- 

 retically developed laws by the examination of the organic remains 

 in the successive geological strata ; and 3rd, the results of these 

 inquiries. 



A few extracts from different portions of the work will show the 

 reader how the author has executed this great problem. The second 

 part commences with these words : — " The crust of the earth is a 

 big book ; its strata are the leaves, its fossils are the letters of the 

 alphabet with which it is written, and its contents are the history 



VOL. XV. PART II. B 



