BRITISH FERTILITY. 211 



together, showing as large dense masses of sticks and 

 twigs. Year after year the young are killed, and yet 

 the rookery is not abandoned, nor the old birds dis- 

 couraged. It is to be added that this species is not 

 the carrion crow, like ours, though so closely resem- 

 bling it in appearance. It picks up its subsistence 

 about the fields, and is not considered an unclean 

 bird. The British carrion crow is a much more rare 

 species. It is a strong, fierce bird, and often attacks 

 and kills young lambs or rabbits. 



What is true of the birds is true of the rabbits, and 

 probably of the other smaller animals. The British 

 rabbit breeds seven times a year, and usually pro- 

 duces eight young at a litter ; while, so far as I have 

 observed, the corresponding species in this country 

 breeds not more than twice, producing from three to 

 four young. The western gray rabbit (Lepus silvat- 

 icus) is said to produce three or four broods a year 

 of four to six young. It is calculated that in Eng- 

 land a pair of rabbits will, in the course of four 

 years, multiply to one million two hundred and fifty 

 thousand. If unchecked for one season, this game 

 would eat the farmers up. In the parks of the Duke 

 of Hamilton, the rabbits were so numerous that I 

 think one might have fired a gun at random with his 

 eyes closed and knocked them over. They scam- 

 pered right and left as I advanced, like leaves blown 

 by the wind. Their cotton tails twinkled thicker 

 than fireflies in our summer night. In the Highlands, 

 where there were cultivated lands, and in various 



