2 THE DOG IN HEALTH. 



of selection of the best was going on, consciously or uncon- 

 sciously. 



There was an ancient race of hounds not very unlike 

 the present swift coursers in essential particulars. Is the 

 breed used in the British Islands in any way related to 

 the Eoman hounds by descent, or have both arisen inde- 

 pendently ? 



The characteristics of the greyhound, then, can not be 

 understood apart from his history, nor from his origin. 

 But regarding him simply as a dog, one of the large family 

 of the Canidce, what has been as yet considered does not 

 explain much. 



Hence the necessity, if we would understand this grey- 

 hound as a dog, to inquire into the origin of the family 

 group to which he belongs. In other words, we must 

 seek for a more distant ancestry and learn if possible its 

 history. 



The subject has been very carefully studied by Charles 

 Darwin, and no better treatment has been given it than 

 may be found in his work, "Animals and Plants under 

 Domestication." Briefly, the origin of the dog has been 

 referred to the following sources : All the various breeds 

 of dogs are believed by some to have descended from 

 some single wild species of animal, while others hold that 

 the evidence of descent from several is stronger. Some 

 think the dog has been derived from several species, ex- 

 tinct and recent, more or less mingled. Some would refer 

 the dog to the wolf, the jackal, or some unknown extinct 

 species. 



No view of the origin of the dog can be considered 

 as proved ; nevertheless, some are much more probable 



