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THE DARKENING SKY. 



remarkable power of changing the color of their skin. This peculiarity depends 

 partly upon the amount of light to which they are exposed, and partly on the emo- 

 tions caused by fear or anger. 



The martens are so common that I am quite sure you do not need any special 

 description, i may say, however, that the pine-marten is so called because it is 

 generally found in places where pine trees abound. It is shy, but is a little fury 

 when driven at bay. The marten is an inveterate thief and robs every bird's nest 

 in its neighborhood, frequently killing the old ones as well as the young. The 

 impudent rogue often takes possession of the nest of a rook, hawk, crow, magpie, 

 or other bird, and you need not be told that his victims dare not attempt to evict him. 



THE BALL-SHAPED ARMADILLO. 



Among my curiosities is a musk-ox, of whose peculiarities many people are 

 ignorant. His chosen home is the frozen regions of the North, and you will find 

 mention of him in the accounts of the voyages of the Arctic explorers. He is 

 without a muzzle, rather small in size, low on his legs, and covered with such an 

 immense quantity of wool and dark- brown hair that he appears to be much larger 

 than he is. During the depth of winter this hair almost touches the ground. 



There is a grayish-white place on his back called the saddle. His large horns 

 are so flattened at the base that they cover his head like a hat, and sometimes 

 weigh fifty or sixty pounds. 



