TRANSMUTABLE. 197 



on the two continents." (Ed. New Phil. Jour- 

 nal, Oct., 1859, page 299.) 



It is this similarity between genera and species 

 which has induced Dr. Hooker to make extensive 

 enquiries into the affinities of plants, the result 

 of which is the adoption of Mr. Darwin's views, 

 at all events in part, by that distinguished 

 botanist. 



But I think that it will be readily admitted 

 that the analogy between plants and animals, 

 so far as this great question of the origin of 

 species is concerned, cannot be sustained. Plants 

 must be subject to the continued effects of 

 crossing, under circumstances to which the ani- 

 mal is not exposed. The conscious principle of 

 the animal, and the instincts implanted in it 

 by nature, must protect, and does protect it 

 from the anomalies which we see effected in the 

 production of the cabbage, the peach, or the 

 apple. And again, we have no proof whatever, 

 that the animal is capable of such changes as 

 those which I have mentioned (and many others 

 could be adduced) in the vegetable world. 



Take, for instance, the dog, or pigeon, or 

 sheep, or ox, and look at the extreme forms of 

 each. There is nothing in them at all approach- 

 ing the difference we see between the cauliflower 

 and the Itrassica oleracea, or the Swedish tur- 

 nip and its source, the Itrassica campestris. 

 Further, I may remark that the principles of 

 diagnosis are not so well defined in plants as 

 in animals, and that there is a much greater 



