INTRODUCTION. 95 



The Tertiary fossils of Italy were made the subject of a 

 masterpiece in pala^ontological literature, Brocchi's l famous 

 monograph, Conchylioloia fossile subapen nina (Milan, 1814). 

 This work comprises two quarto volumes, and is handsomely 

 illustrated with sixteen plates. It begins with a historical 

 review of the development of palaeontology in Italy, depicts 

 in an introductory chapter the structure of the Apennines and 

 the adjoining plains, and distinguishes the Secondary rocks 

 which compose the true mountain-chain from the Tertiary 

 deposits on the lower slopes and plains. The main part of 

 the work is occupied by the specific descriptions of Tertiary 

 mollusca from all parts of Italy. The special locality, the 

 number of specimens, and the particular distribution in sandy 

 or clayey, pelagic, or littoral deposits is accurately recorded 

 for each species; both the descriptions and illustrations are 

 perfect. A special chapter is devoted to the occurrence of 

 land mammals, whales, and fishes. 



Brocchi recognises the great similarity of the Tertiary species 

 of mollusca with species still living in the Mediterranean and 

 Adriatic seas, and likewise the difference between the Italian 

 fossil species and the species of the Paris basin, which had 

 been described by Lamarck and Brongniart. He erroneously 

 attributed the dissimilarity of the Italian and French species, 

 not to any difference in the geologic age, but to the separa- 

 tion of the areas of occurrence. At the same time Brocchi 

 fully realised the fundamental difference between the fossil 

 faunas in the Secondary and Tertiary rocks of his native 

 land. The numerous occurrence of Belemnites, Ammonites, 

 Terebratulas, and other generic types in the Secondary rocks, 

 and their complete absence from the Tertiary faunas is ex- 

 plained on the basis of the gradual extinction of the more 

 ancient types during the vast periods of time that elapsed 

 while successive strata accumulated. 



Brocchi's ideas about the mode of extinction and period of 

 existence of fossil genera and species are of especial interest. 



1 Giovanni Battista Brocchi (born at Bassano in 1772) studied juris- 

 prudence and theology in Padua, was made Professor of Natural History 

 in Brescia, and afterwards Inspector of Mines for the Kingdom of Italy. 

 He travelled through almost the whole of Italy, and published a large 

 number of mineralogical, geological, and paloeontological papers; in 1823 

 he travelled in the East, visited Lebanon and Egypt, and went as an 

 engineer to the Soudan, where he died in 1826 at Khartoum, a victim to 

 the unhealthy climate, 



