Chap. XV, CROSSING AS MODIFYING EACES. 95 



each other, not being liable to this peculiar form of transmission, we may 

 conclude that it is in some way connected with the sudden appearance of 

 the characters in question. 



On the Modification of old Races and the Formation of new Races 

 by Crossing.— We have hitherto chiefly considered the effects of 

 crossing in giving uniformity of character ; we must now look 

 to an opposite result. There can be no doubt that crossing, 

 with the aid of rigorous selection during several generations, 

 has been a potent means in modifying old races, and in forming 

 new ones. Lord Orford crossed his famous stud of greyhounds 

 once with the bulldog, which breed was chosen from being 

 deficient in scenting powers, and from having what was wanted, 

 courage and perseverance. In the course of six or seven 

 generations all traces of the external form of the bulldog 

 were ^ eliminated, but courage and perseverance remained. 

 Certain pointers have been crossed, as I hear from the Eev. 

 W. D. Fox, with the foxhound, to give them dash and speed. 

 Certain strains of Dorking fowls have had a slight infusion 

 of Game blood; and I have known a great fancier who on a 

 single occasion crossed his turbit-pigeons with barbs, for the 

 sake of gaining greater breadth of beak. 



In the foregoing cases breeds have been crossed once, for the 

 sake of modifying some particular character; but with most of 

 the improved races of the pig, which now breed true, there have 

 been repeated crosses,— for instance, the improved Essex owes its 

 excellence to repeated crosses with the Neapolitan, together pro- 

 bably with some infusion of Chinese blood. 21 So with our British 

 sheep: almost all the races, except the Southdown, have been 

 largely crossed; "this, in fact, has been the history of our prin- 

 cipal breeds." 22 To give an example, the « Oxfordshire Downs !y 

 now rank as an established breed.- They were produced about 

 the year 1830 by crossing -Hampshire and in some instances 

 feonthdown ewes with Cotswold rams:" now the Hampshire 

 ram was itself produced by repeated crosses between the native 



« Richardson, 'Pigs/ 1817, pp 37, see also an equally good article by Mr 



♦1 Jv' ? ««n y S t ° f Y ° Uatt ° n Ch - H ° ward ' in ' Gardener's Chronicle ; 

 the Pig, 1860, p. 3. I860, p. 320. ' 



22 See Mr. W. CL Spooner's excellent ^ < Gardener's Chronicle,' 1857 m> 



paper on Cross-Breedmg, ' Journal 649, 652. ' PP " 



Royal Agricult. Soc.,' vol. xx„ part ii. : 



