That the domestic dog has been held in high esteem by mankind from the earliest times, is shown by written records and mummified remains obtained from countries situated widely apart. The statement occurs in the Zendavesta, that "the world exists through the intellect of the dog." Cuvier wrote that "the dog is the completest, the most singular and the most useful conquest that man has ever made * * * each individual is devoted to man and remains attached to him even unto death; and all this springs not from necessity nor from fear, but from a true friendship. The dog is the only animal that has followed man all over the globe." Egyptian monuments dating back 3,400 years B. C., show several varieties of dogs, most of them being allied to the greyhound. Carved records of a later period portray the mastiff, a turnspit and a form closely resembling the hound. Without question the dog was domesticated in Europe previous to any historical record. His remains are found in the kitchen-middens of Neolithic times and an increasing size in the animals is noticed through the Bronze and Iron ages in Denmark. Remains of the Neolithic in Switzerland disclose skulls closely resembling our hounds, setters or spaniels. The Americans had indigenous dogs before the conquering Spaniards introduced European species, and mummies of dogs are found in the oldest Peruvian tombs. All this goes to show that the differentiation of the dog took place at a very early date. As in the case of man, the link is missing, but the ancestry is certain. Without question the varieties of the dog originated in domestication and inter-breeding of different species of wolves living in various parts of the world. The dog family is divided into three groups. First, the wolves or wild dogs, having a round pupil in the eye and a short tail. Second, the foxes, which are characterized by a slit-like pupil and a long bushy tail; and, third, the long-eared dogs which inhabit eastern deserts and possess more numerous and a different set of teeth than the other groups. Considered as a family they are distinguished by a lean body, small head, the slim or long legs terminated by small paws furnished with strong but not retractile claws. The fore paws usually have five toes while the hind paws are always limited to four. As the dogs do not live exclusively on animal food they are not as savage as the cats, neither do they possess the "soulless expression of face so characteristic of the felidae." While most of the dog family are gregarious, certain forms lead lives that are solitary or nearly so. Other species are nocturnal in their habits, while yet others burrow in the earth for shelter or protection. All bend the joints of the legs in walking, all possess great speed and endurance, and without exception are good swimmers.