316 MISCELLANEOUS OBJECTIONS TO THE [Chap. VII. 



in the larger genera are more closely related to each 

 other, and present a greater number of varieties than do 

 the species in the smaller genera. The former are also 

 grouped in little clusters, like varieties round species ; 

 and they present other analogies with varieties, as was 

 shown in our second chapter. On this same principle 

 we can understand how it is that specific characters are 

 more variable than generic characters ; and how the 

 parts which are developed in an extraordinary degree or 

 manner are more variable than other parts of the same 

 species. Many analogous facts, all pointing in the same 

 direction, could be added. 



Although very many species have almost certainly 

 been produced by steps not greater than those separat- 

 ing fine varieties ; yet it may be maintained that some 

 have been developed in a different and abrupt manner. 

 Such an admission, however, ought not to be made 

 without strong evidence being assigned. The vague 

 and in some respects false analogies, as they have been 

 shown to be by Mr. Chauncey Wright, which have been 

 advanced in favour of this view, such as the sudden 

 crystallisation of inorganic substances, or the falling of 

 a facetted spheroid from one facet to another, hardly 

 deserve consideration. One class of facts, however, 

 namely, the sudden appearance of new and distinct 

 forms of life in our geological formations supports at 

 first sigh: the belief in abrupt development. But the 

 value of this evidence depends entirely on the perfection 

 of the geological record, in relation to periods remote in 

 the history of the world. If the record is as fragmentary 

 as many geologists strenuously assert, there is nothing 

 strange in new forms appearing as if suddenly developed. 



Unless we admit transformations as prodigious as 



