468 



ZOOLOGY 



Microscopic 

 life in the 

 north 



Vertebrate 

 animals of 

 the north 



the midst of the antarctic continent there is no such 

 source of food, and consequently life is practically 

 confined to areas near the coast. Were the tempera- 

 ture of the whole earth to fall to that of the polar 

 regions, life would persist in the oceans and along the 

 coasts of the continents, but the interior uplands would 

 be barren and desolate. 



3. Nansen tells us how he found the arctic ice 

 teeming with thousands of millions of microscopic 

 organisms. The sun melts the snow, forming pools 

 on the ice, and these soon show yellowish-brown spots, 

 at first small, but gradually increasing in size. These, 

 under the microscope, are seen to consist of minute 

 plants, principally diatoms. Each spot represents an 

 enormous population, a little city of these simple 

 organisms. Also present, feeding on the plants, are 

 many different kinds of protozoa. Thus the frozen 

 north, apparently so barren, is really full of life, - 

 life which prospers and finds no hardship in the con- 

 ditions which exist. Under the ice, in the sea, are many 

 other creatures. 



4. The higher, more conspicuous life of the north is 

 much better known. Every one has heard of the 

 polar bear, the walrus, the arctic fox, and the musk ox 

 of Greenland. So also there are many birds, some of 

 them common visitors to more southern regions in the 

 winter. The beautiful Ross's gull, with rosy breast, 

 is called by Nansen a "rare and mysterious inhabitant 

 of the unknown north, only occasionally seen, and 

 no one knows whence it cometh or whither it goeth." 

 Some of the arctic animals are white, like their surround- 

 ings, others quite the reverse. To be white is to escape 

 observation, as when the polar bear creeps soft-footed 

 toward the seal ; but the musk oxen, living in herds, 



