408 LECTURE XIV. 



original forms whicli we distinguisli as well-establislied species. 

 And tliis is really tlie case. If at this day the badger-dog 

 were only found in a fossil state^ that is to say, in a condition 

 which would give us no clue as to the origin of its deformed legs, 

 every naturalist would at once declare it a distinct species of 

 dog. The UruSj the marsh-cow, the curved-horned cattle, were 

 all by naturalists, like Cuvier, Owen, Mlsson, and others, distin- 

 guished as diflFerent species so long as they were only found in 

 the diluvial formations of various countries, and until the present 

 races of cattle were proved to be their descendants. Concern- 

 ing these races, all physiologists, ignorant of their connection 

 with the extinct races, maintained that they all belonged to 

 the same species — the Bos taurus, and tried, with much inge- 

 nuity, to prove that they must all have originated from the 

 same parent stock. This proof was founded upon the circum- 

 stance that the artificial breeds, the production of which 

 occurred in historical times, differ not less in their characters 

 than the older races, the origin of which is lost in obscurity. 

 They were perfectly right as regards the latter point; they 

 only failed to draw a correct inference, namely, that the same 

 sum of distinctive characters which seems to us sufficient for 

 the establishment of a species, could also, within historical 

 times, have been produced by individual transmission ; that it 

 is, therefore, in the power of man, and of present nature, to 

 produce from existing species new varieties, races, and real 

 new species. 



Just as the artificial breeds depend on their profitableness, 

 being only preserved by the selection of such individuals as 

 are in the fullest possession of useful qualities, so will 

 the natural race, produced by the individual transmission 

 of some prominent characters, be only preserved and further 

 developed when these qualities are in accordance with the 

 requirements of the animal in its struggle for existence. 

 Artificial and natural races run, in this respect, perfectly 

 parallel, and the only discoverable difierence seems to be that 

 man, though he cannot use unnatural means, has the power of 

 selecting, in preference, some natural influences. Let us just 



