Another important feature, little understood, and frequently much dreaded, is that of Antecedent Impressions.  When a bitch has been served by a dog not of her own breed it has been proven in extremely rare cases that the subsequent litters by dogs of her own kind, showed traces (or, at least, one or more of the litter did) of the dog she was first lined by.  The theory by physiologists is that the life-giving germ, implanted by the first dog, penetrates the serous coat of the ovary, burrows into its parenchyma, and seeks out immature ova, not to be ripened and discharged perhaps for years, and to produce the modifying influence described.  Many breeders are unwise enough to believe that a bitch the victim of misalliance is practically ruined for breeding purposes and discard her.  While, of course, we believe in the fact of Antecedent Impressions, we think they are as rare as the proverbial visit of angels.  We have given this subject serious attention and have tried numerous experiments, using various dogs to ward our bitches, including a pug, spaniel, wire-haired fox terrier, pointer, and perhaps one other, and we have never seen a trace of these matings in subsequent litters.  One case, for example:  In another part of this book we allude to a dog spoken of by Dr. Mott, in his “Treatise of the Boston Terrier,” named “Muggy Dee.”  The grandmother of this charming little dog was bred in our kennels, by name, “St. Botolph’s Bessie.”  We sold her to a Boston banker, and she matured into a beautiful dog.  Upon coming in season she was unfortunately warded by a spaniel on the estate, which so disgusted her owner that he gave her to the coachman.  She proved a perfect gold mine to him, as she raised two litters of elegant ideal Bostons every twelve months for a great number of years, and never at any time showed any result of the misalliance.

On the subject of Mental Impressions we need say but little, as the chances of it ever taking place are so small that we merely give it a passing notice and say that in all our experience we have never been troubled with a case.  For the benefit of the uninitiated will briefly state that this consists of the mental impression made on the mind of a bitch by a dog with whom she has been denied sexual intercourse, affecting the progeny resulting from the union of another dog with the bitch, generally in regard to the color, and this strange phenomena, when it does occur, is apt to mark usually one puppy of each litter.

A fact not generally known by breeders is that if a bitch is lined by a second dog at any time during heat, the chances are that a second conception may take place, resulting in two distinct sets of pups, half-sister or brother to each other.  This fact we have proven.