Breeds and Varieties 23 



notably the Leghorn, foreign blood has been in- 

 troduced which has modified, to some extent, the 

 laying propensities. At first thought the prac- 

 tice of introducing the blood of an alien breed in 

 the formation of a new variety of an egg breed 

 would be condemned; but when it is once well 

 understood that crossing within certain limits 

 brings increased vigor to the progeny, it may be 

 seen that for egg production alone the new va- 

 riety, which is given a little more robustness, 

 may be made to produce as many eggs by a pro- 

 cess of moderately-forced feeding as the some- 

 what more delicate pure breed whose inherent 

 tendency to egg production may be a little 

 stronger. 



Leghorn. This is one of the Mediterranean 

 breeds whose name is supposed to have been de- 

 rived from the city of Leghorn in Italy, whence 

 they are thought to have been brought to Amer- 

 ica. The early history of the breed is now more or 

 less obscure, and this is due, no doubt, in a large 

 degree, to the fact that they were unpopular for 

 many years after they were introduced into this 

 country. Although they are credited with being 

 introduced in the early part of the nineteenth 

 century, it was not until after the middle of the 

 century that they attracted much attention. As 

 the popular animals and crops are most written 

 about, it is not strange that a more or less un- 



