184 OUR HUMBLE HELPERS 



close resemblance between individuals of the same 

 species, and symmetry of coloring on the two halves 

 of the body. As one is, so are all, with very slight 

 exceptions ; as is the right side, so is the left. Who- 

 ever has seen one wolf has seen all wolves ; whoever 

 has seen from one side an animal with variegated 

 coat has seen both sides. One of the most constant 

 effects, therefore, of domestication is the replacing 

 of this primitive regularity in color by irregularity, 

 this similarity in individuals by dissimilarity. 



"The dog's coat goes contrary to every rule except 

 in one most curious respect : if the animal is spotted 

 with white, one of these white spots is always on the 

 end of the tail. Examine a black dog, for example : 

 if you see so much as one white speck on it, no matter 

 where, on the flank, or on the shoulder, you will be 

 sure to see one where I told you. Look at the end 

 of the tail and you will find at least a touch of white 

 there." 



"So it is enough to see some white on any part of a 

 dog to be sure that it will have some also on the tip 

 of its tail?" This from Jules. 



* ' Certainly, " replied his uncle, "unless, of course, 

 the animal has had its tail cut, in which case I will not 

 answer for it." 



"That is plain enough: with the tip of the tail 

 missing the white touch is missing too." 



"I will add that if the dog has only one white spot, 

 that spot will always be on the tip of the tail." 



"That singularity must have a reason!" queried 

 Louis. 



