INFLUENCE OF CLIMATE, 4Q;|^ 



with the laws of climate, we find nature ready to aid us. The 

 Spanish Merino found its New England home quite as congenial 

 as the one it left in old Spain, and consequently the improved type 

 of that animal now known among us yields a fleece three times as 

 heavy as that produced by its best Spanish progenitor. 



It is the opinion of the great naturalist, Darwin, that the heavy 

 breeds of cattle and sheep now known in England could never 

 have been formed on mountainous pastures, nor could dray-horses 

 have been raised on barren and inhospitable islands. The short 

 pastures and humid climate of the Falkland Islands will in a few 

 generations convert the stout horse into a diminutive pony. The 

 European dog, transported to India, becomes changed, not only 

 in structure, but in his instinct even. Within so "narrow tei-rito- 

 rial limits as England a difference in the quality of the wool has 

 been noticed when the same flock of sheep have been pastured in 

 different localities. At Angora, nature clothes not only the goat 

 but the cat and the dog even in fine fleecy hair ; and we have it 

 on good authority, that horses kept for a series of years in the 

 deep coal mines of Belgium become covered with velvety hair 

 like the mole. 



Thus the organic history of the past, not less than scientific 

 observations of the present, teach that forms in both vegetable 

 and animal organizations i^e dependent upon the material condi- 

 tions under which they live, and that any change in these environ- 

 ments imprints a corresponding change upon their form and 

 structure. In the one, whether living or dead, we read unerringly 

 the variations of the other, and hence we arrive at the important 

 conclusion that, in order to secure permanency to any typical 

 form, we must first ensure invariability to the physical conditions 

 in which it exists. Thus we learn that in ages far remote, leaf 

 and flower, beast and bird, quietly laid down their lives in obe- 

 dience to laws whose demands they could not meet, faithfully 

 imprinting their perishing forms upon the plastic materials of earth 

 — a truthful history of the orderly procedure of nature. 



Answering to the voice of the same great power which bade the 

 old depart, new forms of life have* come forth to find a congenial 

 home in each new epoch of the earth's development. We are told 

 that "If some grains of sand lie scattered on a drum head or some 

 other elastic surface, whenever a suitable sound is made the grains 

 start up, and entering on a choral dance, arrange themselves in 

 symmetrical and exquisitely perfect geometrical figures. If dis- 

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