116 A CENTURY OF SCIENCE 



that some of them were extinct. These views then led to 

 many fantastic theories as to how the earth was formed 

 dreams, most of them have been called. Marsh says : 



"The dominant idea of the first sixteen centuries of the 

 present era was, that the universe was made for Man. This was 

 the great obstacle to the correct determination of the position 

 of the earth in the universe, and, later, of the age of the earth. 

 . . . In a superstitious age, when every natural event is 

 referred to a supernatural cause, science cannot live . . . 

 Scarcely less fatal to the growth of science is the age of Author- 

 ity, as the past proves too well. With freedom of thought, came 

 definite knowledge, and certain progress; but two thousand 

 years was long to wait." 



One of the most significant publications of this period 

 was Linnaeus 's Systema Naturae, which appeared in 1735. 

 In this work was introduced binomial nomenclature, or 

 the system of giving each plant and animal species a 

 generic and specific name, as Fells leo for the lion. The 

 system was, however, not established until the tenth 

 edition of the work in 1758, which became the starting 

 point of zoological nomenclature. Since then there has 

 been added another canon, the law of priority, which 

 holds that the first name applied to a given form shall 

 stand against all later names given to the same organism. 



Catastrophic Period. With the beginning of the nine- 

 teenth century there started a new era in paleontology, 

 and this was the time when the foundations of the science 

 were laid. The period continued for six decades, or until 

 the time of the Origin of Species. Marsh says that now 

 "method replaced disorder, and systematic study super- 

 seded casual observation." Fossils were accurately 

 determined, comparisons were made with living forms, 

 and the species named according to the binomial system. 

 However, every species, recent and extinct, was regarded 

 as a separate creation, and because of the usually sharp 

 separation of the superposed fossil faunas and floras, 

 these were held to have been destroyed through a series 

 of periodic catastrophes of which the Noachian deluge 

 was the last. 



Lamarck between 1802 and 1806 described the Tertiary 

 shells of the Paris basin. Comparing them with the liv- 



