On the Variations of certain Crustacea. 337 



these, which, from tile requirements of natural selection, must 

 be but seldom, he immediately answers that the two extreme 

 forms are not good species, but only varieties. This is a 

 vicious style of argument. Darwin rightly says that facts 

 seems to prove the fruitfulness or sterility of animals inter se, 

 to be a criterion of no value whatever, but his opponents 

 maintain that the descendants of varieties are fruitful, and of 

 species sterile, inter se. So when Rouy in Angoulerne obtained 

 many successive generations of a breed between the hare and 

 the rabbit, they directly affirm that these animals had been 

 hitherto misunderstood, and that they are evidently only varie- 

 ties of the same species. In the same way, however, as we 

 discriminate species by characters occurring either singly or 

 in combination, we are entitled to believe in the general un- 

 fruitfulness together of animals belonging to those forms which 

 we designate by the name of species — a peculiarity imparted 

 to them along with many other characters, and having in itself 

 nothing requiring separate explanation." 



A great many people fear to believe in the derivative origin 

 of species, because they vaguely fancy that the doctrine leads 

 to materialism, and even worse phases of belief or unbelief. 

 They charge its advocates with inability to appreciate what- 

 ever cannot be weighed and handled, with a want of reverence 

 for the spiritual and unseen. And, indeed, it is obvious that 

 material organisms must be subject to the laws which regu- 

 late matter, just as much as spiritual entities must obey the 

 laws of spirit. But though we believe that the phenomena of 

 origin and creation are the result of the operations of immu- 

 table law, no less as regards species and races than as regards 

 the individual ; we believe likewise that these laws are at once 

 an expression of the will, and a revelation of the wisdom of 

 the Eternal, and that through them " the whole round earth is 

 everyway bound by gold chains about the feet of God." 



VOL. X. — V,0. Y. 



