108 THE ORIGIN OF SPECIES 



the extinction of any particular species or group of 

 species. 



O71 the Forms of Life changing almost simultaneously 

 throughout the World 



Scarcely any paleontological discovery is more striking 

 than the fact that the forms of life change almost simul- 

 taneously throughout the world. Thus our European 

 Clialk formation can be recognized in many distant 

 regions, under the most different climates, where not 

 a fragment of the mineral chalk itself can be found; 

 namely, in North America, in equatorial South America, 

 in Tierra del Fuego, at the Cape of Good Hope, and in 

 the peninsula of India. For at these distant points, the 

 organic remains in certain beds present an unmistakable 

 resemblance to those of the Chalk. It is not that the 

 same species are met with; for in some cases not one 

 species is identically the same, but they belong to the 

 same families, genera, and sections of genera, and some- 

 times are similarly characterized in such trifling points 

 as mere superficial sculpture. Moreover, other forms, 

 which are not found in the Chalk of Europe, but which 

 occur in the formations either above or below, occur in 

 the same order at these distant points of the world. 

 In the several successive paleozoic formations of Russia, 

 Western Europe, and North America, a similar parallel- 

 ism in the forms of life has been observed by several 

 authors; so it is, according to Ly ell, with the European 

 and North American tertiary deposits. Even if the few 

 fossil species which are common to the Old and New 

 Worlds were kept wholly out of view, the general paral- 

 lelism in the successive forms of life, in the paleozoic jl 



