GEOGRAPHICAL DISTRIBUTION OF ANIMALS 1545 



the gregarious tribes of edible fish, as the cod, turbot, 

 mackerel, herring, pilchard, and many others. The 

 stromming of the Baltic is of like utility. The 

 salmon frequents the estuaries and river-mouths 

 throughout the coast-line of Western Europe to the 

 northward of the Bay of Biscay, becoming more nu- 

 merous as higher latitudes are reached. 



The generally temperate climate of Europe 

 secures it, for the most part, an exemption from the 

 dense swarms of insect-life that belong to warmer 

 latitudes. Yet between eight or nine thousand species 

 are enumerated as native to the British Islands alone. 

 The common honey-bee is distributed all over south- 

 ern and Central Europe, and is probably indigenous. 

 The locust is only an occasional visitor to its shores, 

 and belongs to the other side of the Mediterranean. 

 The silk-worm was introduced from China toward 

 the close of the Fifth Century of our era. 



Asia is rich in variety of animal life, and especially 

 so as regards the class mammalia, all the orders of 

 which but two (the marsupials and the edentata) are 

 represented in its zoology. Of domesticated quadru- 

 peds, the camel, ox, goat, and sheep, among the rumi- 

 nants, with the horse, the ass, and the elephant, among 

 pachyderms, are natives of Asia. The camel, of 

 which there are several species, all natives of this 

 continent, ranges from the shores of the Indian Ocean 

 and Red Sea as far north as Lake Baikal. The rein- 

 deer and elk frequent the Siberian and Mongolian 

 plains, migrating from the former locality southward 

 with the approach of winter. Numerous varieties of 

 the ox tribe (including the common ox, aurochs, buf- 



