478 Recent freshwater Molhisca^ 



position that species alone are permanent, whilst everything 

 else is subject to change ; for were they transmutable, it would 

 be in the course of the long periods, and during the progress 

 of the important changes which the geologist notes ; so that 

 whether these fragments be regarded as formerly identical, 

 but at present distinct from existing forms, or as distinct at all 

 times, the general result and its applications remain undis- 

 turbed. 



Mr. Lyell lays great stress (vol. ii. p. 369) upon the fact 

 that Lamarck does not cite the appearance of any new or- 

 gan^ but I have endeavored to show, that the theory is not 

 dependent upon the production of any organ not already ex- 

 isting in an undeveloped state. His remarks against appe- 

 tency are well directed ; but the idea, in the extent to which 

 it has been carried, should be discarded as more detrimental 

 than useful to those who maintain the instability of species ; 

 because whilst its connection with the subject is very slight, 

 the discussion of it has a tendency to turn the unthinking in- 

 quirer aside from the true and philosophical basis of this im- 

 portant question, leading him to believe that if appetency 

 be disproved, transmutation falls with it. The objection 

 (p. 375) that numerous links in the animal series are wanting, 

 has not much force, as there are many causes to remove 

 them, or prevent them from becoming permanently estab- 

 lished ; and the original creation may have included a mul- 

 titude of beings of all classes. Moreover, the species of the 

 vertebrata and articulata may be comparatively stationary, 

 and the molluscous division peculiarly liable to transmutation 

 and hybridity. The reason why the lower orders still exist, 

 is to be looked for in the fact that they are fitted for the cir- 

 cumstances under which we find them. The researches of 

 Professor Forbes, in the Grecian archipelago, prove that whilst 

 some species are gradually verging towards extinction, oth- 

 ers, belonging to a more recent period, are gradually increas- 

 ing in numbers. 



I pretend not to ofTer an opinion for or against the 

 lamarckian hypothesis, being more anxious to show the in- 



