Natural History of the United States. 253 



the doctrine of the creation of animals ; but to what is it that 

 creation refers ? — not to genera and higher groups, they express 

 only the relations of tilings created, — not to individuals as now 

 existing, they are the results of the laws of invariability and in- 

 crease of the species, — but to certain original individuals, proto- 

 plasts, formed after their kinds or species, and representing the 

 powers and limits of variation inherent in the species — the poten- 

 tialities of their existence, as Dana well expresses it. The spe- 

 cies, therefore, with all its powers and capacities for reproduction, 

 is that which the Creator has made, his unit in the work, as well 

 as ours in the study. The individuals- are merely so many masses 

 of organised matter, in which, for the time, the powers of the spe- 

 cies are embodied ; and the only animal having a true individu- 

 ality is man, who enjoys this by virtue of mental endowments, 

 over-ruling the instincts which in other animals narrowly limit 

 the action of the individual. To this great difference between the 

 limitations imposed on animals by a narrow range of specific 

 powers, and the capacity for individual action which in man forces 

 even his physical organisation, in itself more plastic than that of 

 most other animals, to bend to his dominant will, we trace not 

 only the varieties of the human species, but the changes which 

 man effects upon those lower animals which in instincts and con- 

 stitution are sufficiently ductile for domestication. 



Thirdly, the species is different, not in degree, but in kind, from 

 the genus, the order, and the class. "We may recognise a generic 

 resemblance in a series of line engravings representing different 

 subjects, but we recognise a specific unity only in those struck 

 from the same plate ; and no one can convince us that the resem- 

 blance of a series of coins, medals, or prints, from different dies or 

 plates, is at all of the same kind with that which subsists between 

 those produced from the same die or plate. In like manner, the re- 

 lation between the members of the brood of the song sparrow of 

 this spring, is of a different kind as well as different degree from 

 that between the song sparrow and any other species of sparrow. 

 So of the brood of last year to which the parent sparrows may 

 have belonged ; so by parity of reasoning of all former broods, and 

 all song sp irrows everywhere. The species differs from all other 

 groups in not being an ideal entity, but consisting of indivi- 

 duals struck from the same die, produced by continuous repro- 

 duction from the same creative source. Nor need we suppose 

 with our author — for as yet it is merely an hypothesis — that spe- 



