THE PHENOMENA OF ORGANIC NATURE. 139 



win's views have one peculiar merit ; and that is, that 

 they are perfectly consistent with an array of facts which 

 are utterly inconsistent with and fatal to, any other 

 hypothesis of progressive modification which has yet 

 been advanced. It is one remarkable peculiarity of 

 Mr. Darwin's hypothesis that it involves no necessary 

 progression or incessant modification, and that it is 

 perfectly consistent with the persistence for any length 

 of time of a given primitive stock, contemporaneously 

 with its modifications. To return to the case of the 

 domestic breeds of pigeons, for example ; you have the 

 Dove-cot pigeon, which closely resembles the Rock 

 pigeon, from which they all started, existing at the 

 same time with the others. And if species are devel- 

 oped in the same way in nature, a primitive stock and 

 its modifications may, occasionally, all find the con- 

 ditions fitted for their existence ; and though they 

 come into competition, to a certain extent, with one 

 another, the derivative species may not necessarily ex- 

 tirpate the primitive one, or vice versa. 



Now palaeontology shows us many facts which are 

 perfectly harmonious with these observed effects of the 

 process by which Mr. Darwin supposes species to have 

 originated, but which appear to me to be totally in- 

 consistent with any other hypothesis which has been 

 proposed. There are some groups of animals and 

 plants, in the fossil world, which have been said to 

 belong to " persistent types," because they have per- 

 sisted, with very little change indeed, through a very 

 great range of time, while everything about them has 

 changed largely. There are families of fishes whose 

 type of construction has persisted all the way from the 

 carboniferous rock right up to the cretaceous ; and 



