THE SHEEP. 173 



dam's neck ; and at this it will continue sucking for an 

 indefinite time. It is highly probable that the strong- 

 smelling secretion of the sheep's udder attracts the lamb 

 at length to that part ; and without something of the 

 kind to guide it, in many cases it would actually starve 

 without finding the teats. I have often seen lambs many 

 hours after birth still confining their attention to the 

 most accessible locks of wool on the neck or fore-legs of 

 the dams, and believe that in such cases the long time 

 it took them to find the source of nourishment arose 

 from a defective sense of smell. 



Now there is one important physiological law 

 which has of late come into prominence, which 

 has a marked bearing upon the question Mr Hud- 

 son raises. This is the law that nervous pheno- 

 mena, such as instincts, reflexes, and the like, 

 are much more fixed and permanent in the animal 

 economy than are details of structure in the skin, 

 muscles, or skeleton. When we find that all our 

 domestic animals, with the one exception of the 

 sheep, are capable of resuming their original inde- 

 pendence without difficulty, in spite of thousands 

 of years of domestication during which the many 

 complex and delicate instincts necessary for wild 

 life lay dormant, one is very reluctant to accept 

 the theory as to a natural instinct having been 

 perverted or abolished by domestication. It is 



