MAMMALIA 231 



varied; here their favorite haunts are markets, restaurants and other 

 places where food is stored, especially in the neighborhood of docks 

 and wharves. A large milling company of Kentucky estimated its 

 annual loss upon grain sacks alone at $3000 and in smaller mills 

 it is common to hear the manager estimate his annual loss at many 

 hundreds of dollars. 



"In 1898 a large packing house in Chicago had 3360 hams de- 

 stroyed by rats;" and in the smaller branch offices of the packing houses, 

 where thorough rat proofing has not been adopted, heavy losses to 

 meat are reported. 



Commission merchants suffer heavily from rats, which eat all kinds 

 of goods and carry off eggs by the dozen in a single night. 



The department stores, especially those that handle food-stuffs, 

 as most of them do, suffer so heavily that most of them regularly em- 

 ploy, by the year, professional rodent exterminators that they pay often 

 as much as $50 or more a month. Besides eating and spoiling 

 large quantities of food-stuffs the rat does heavy damage in various other 

 ways; for example, numerous fires have been started from rats and mice 

 gnawing matches; buildings have been flooded by rats gnawing through 

 lead water-pipes; expensive china and glassware are sometimes knocked 

 from shelves and broken; bedding, furniture, drygoods and other in- 

 edible materials are often destroyed or rendered unsalable. 



Few people realize the numbers of rats that are sometimes found 

 in infested regions. After careful and conservative investigation it has 

 been estimated that in towns the normal rat population is about equal 

 to the human, while in rural districts it is much greater. On a rice 

 plantation of 400 acres over 17,000 rats were killed in a single year. 

 In a single raid in a city warehouse often bushels of rats are destroyed. 

 1700 rats have been destroyed in fumigating a steamship. 



Under certain conditions rats have been known to migrate in great 

 hordes, like their relatives, the lemmings; and there is a more or less 

 definite periodic migration from their warm winter quarters in towns 

 and buildings to the adjoining fields, and back again, with the change of 

 seasons. 



Being secretive and largely nocturnal in habits there are often many 

 more rats about a certain region than is generally appreciated, and this, 

 added to their remarkable cunning, enables them to multiply with as- 

 tonishing rapidity. 



