214 THE BOOK OF THE ANIMAL KINGDOM 



has this well-hated pest been carried to different parts of the world 

 on board ship, but it is authentically recorded to have swum rivers 

 and seas in immense numbers, and so set up a colony in another 

 clime. Not content with thus establishing itself, the Brown Rat has 

 waged incessant war with the Black species, and both in England 

 and on the Continent has almost successfully exterminated it ! 



This voracious beast will eat almost anything. Nothing seems 

 to come amiss to it, the veriest filth imaginable being greedily 

 relished. It is only fair to notice that on occasions it is an animal 

 scavenger, eating carrion, refuse, etc., but grain, eggs and young 

 birds, young rabbits, fish and other creatures are also devoured. It 

 is often found near and in water, and is stupidly referred to as the 

 Water Rat, being confused with the dapper and innocent Water 

 Vole, one of the cleanest and happiest little fellows under the sun. 

 The misdeeds of the Brown Rat are, I venture to assert, often 

 erroneously attributed to the herbivorous Water Vole, a delightful 

 Beaver-like rodent whose antics in and around the water will amply 

 repay observation. 



One great reason why the Brown Rat multiplies and spreads so 

 rapidly, when once it has become firmly established, is its extra- 

 ordinary fecundity. It breeds from three to six times a year, the 

 female first giving birth when she is only about three months old. 

 As a rule the litter consists of about ten young ones, although this 

 is only a fair average, and larger families are often reared. A simple 

 calculation may be made to illustrate how rapidly this mammal can 

 multiply its numbers, for if we calculate three litters of ten each 

 being produced every year, a single pair, if left alone, would, in the 

 short period of three years, have a progeny of ten generations, 

 numbering no less than twenty million, one hundred and fifty-five 

 thousand, three hundred and ninety-two. Whilst if the sum be 

 carried a little further, we find that the eleventh generation, due at 

 the beginning of the fourth year, would number over one hundred 

 millions ! 



It is calculated that in France alone the Brown Rat is responsible 

 for at least ;^8,ooo,ooo worth of damage every year, for it not only 

 eats two ounces of corn every day, but destroys quite as much as, 

 if not more than, it eats. Both in the United States and in England 

 efforts have been made to eradicate this, the worst of all mammalian 

 pests, but the animal is still plentiful almost everywhere. 



The greatest sin attributed to it— even if the enormous damage 



