240 CROSSING AND CLOSE-INTERBEEEDING. 



and that any return to such type, whether effected by 

 direct Reversion, by Crossing, or by Grafting, is at- 

 tended by a physiological regain, or abatement of the 

 evils entailed by the loss or reduction of characters. 



The space available would not suffice for all the 

 proofs on hand; so, it has been deemed advisable, 

 merely, to furnish evidence respecting one or more of 

 those species which principally illustrate either of the 

 four more pronounced modes of Selection. 



Pigeons and Fowls constitute the subject of one 

 Chapter, because they both represent the mode of 

 Selection by which lost characters, of a species, are 

 indeed all regained, but regained only to be apportioned 

 among distinct varieties, and not developed, all, in each 

 variety. 



Pigs form the subject of another Chapter, because 

 they represent that mode of Selection, pursued by 

 breeders, by which characters, of a species, instead of 

 being developed, are reduced and suppressed. 



Horses, Sheep, and Cows constitute the subject of 

 another Chapter, because they represent the mode of 

 Selection by which the lost and. reduced characters, of 

 a species, are (comparatively speaking) all concurrently 

 regained and re-developed in each individual or variety, 

 and a very close approximation to the full and pro- 

 portionate development of all the parts, of a species, 

 effected. 



Plants form the subject of another Chapter, because 

 they illustrate the effects flowing from that mode of 

 Selection which develops to a great, or to the extreme 

 point, one only of the characters of a species; and, 



