Ixvi INTRODUCTION. 



who had been disciplined to the act. The young terrier, the 

 first time he sees a rabbit, will track him to his burrow ; the 

 young water-spaniel will strive to seize the objects which he 

 sees floating in the stream, though he has never before be- 

 held a rivulet ; the young bull-dog will fly at the throat of 

 the first animal that assails him. The race-horse, to whom 

 we have communicated the conformation which suits him for 

 rapid motion, will manifest the fiery spirit proper to him, by 

 his mother's side, a few hours after birth. The Arabian 

 horse, with his broad and high forehead, indicating a larger 

 development of the brain, manifests a far superior sagacity 

 to the humbler horse of inferior lineage. Of the breeds of 

 the domestic sheep, some are acclimated in countries of heaths 

 and mountains, and some in the richer plains. Each has 

 acquired the conformation which suits him to these condi- 

 tions. If we take the mountain-lamb from its mother's teat 

 at the very birth, and bring it to the valley below, we shall 

 find it still, when grown to maturity, prefer the smaller 

 grasses, the wild thyme, and other plants of mountains, to 

 the richer herbage, and betake itself to the arid eminences 

 of its pasture-fields in preference to the sheltered hollows, 

 and communicate these desires to its offspring. Are not 

 such propensities as these mental, and the result of a con- 

 formation of the animal organs, and consequently transmis- 

 sive from the parents to the young ? Thus, habits acquired 

 may assuredly be communicated from animal to animal. We 

 cannot indeed suppose that a young puppy would turn a spit, 

 or dance to a tune, because its parents had been taught to 

 do so, but we can suppose that if a race of dogs had been 

 compelled, from generation to generation, to dance and turn 

 spits, they would acquire the conformation which would suit 

 them to perform these offices ; which would be nothing more 

 than one of innumerable examples of the progressive adap- 

 tation of the form of animals to the uses to which they are 

 habituated. 



Even mutilation of the body may, in certain cases, produce 



