592 HISTORY OF GEOLOGY. 



doctrine, those mountain ranges, even in distant 

 parts of the world, which are of the same age, 

 according to the classifications already spoken of, 

 are asserted to be parallel 4 to each other, while 

 those ranges which are of different ages lie in dif- 

 ferent directions. This very wide and striking pro- 

 position may be considered as being at present upon 

 its trial among the geologists of Europe (CA). 



Among the organic phenomena, also, which have 

 been the subject of geological study, general laws 

 of a very wide and comprehensive kind have been 

 suggested, and in a greater or less degree confirmed 

 by adequate assemblages of facts. Thus M. Adolphe 

 Brongniart has not only, in his Fossil Flora, repre- 

 sented and skilfully restored a vast number of the 

 plants of the ancient world ; but he has also, in the 

 Prodromus of the work, presented various import- 

 ant and striking views of the general character of 

 the vegetation of former periods, as insular or con- 

 tinental, tropical or temperate. And M. Agassiz, 

 by the examination of an incredible number of 

 specimens and collections of fossil fish, has been led 

 to results which, expressed in terms of his own ich- 

 thyological classification, form remarkable general 

 laws. Thus, according to him 5 , when we go below 

 the lias, we lose all traces of two of the four orders 



4 We may observe that the notion of parallelism, when applied 

 to lines drawn on remote portions of a globular surface, requires 

 to be interpreted in so arbitrary a manner, that we can hardly 

 imagine it to express a physical law. 



b Greenough, Address to Geol. Soc. 1835, p. 19. 



