TWO widely-spread "beliefs"—in regard to the complicated and not generally familiar subject of the reproduction of animals—are, in addition to that dealt with in the last chapter, examples of the unjustified and primitive mode of forming a conclusion known as "post hoc ergo propter hoc." I refer, firstly, to the belief (which I have already mentioned) in the causation of what are called "birth-marks" by "maternal impressions," by which is meant the seeing of unusual and impressive things by the mother when with child; and, secondly, to the belief that a thoroughbred mare can be so affected or infected by the sire (say a zebra) of one foal as to convey to the foal of a later sire (say, a thoroughbred like herself) marks (such as stripes on the legs) which were not present in the second sire, though present in the first sire. This supposed occurrence is called "telegony," and is by some persons supposed to occur in dogs, cattle, and other animals, including man, as well as in the horse. There is little support in ordinary experience for the belief that birth-marks are caused by maternal impressions, although some of those who are concerned in a professional way with breeding operations cling to it. In very ancient times we find that there was a belief in But this unwarranted, untested belief, originating among barbarous peoples, has led further, owing to the inveterate love of marvels still common among us, to the notion (surviving to the present day) that the irregular coloured or obscure marks sometimes found on the skin of a child at birth, and vaguely resembling an animal or a fruit, or what not, are due to the mother having recently seen, under some sudden and startling circumstances, the object which the "birth-mark" on the child resembles. Thus we have the following stories related in a recent publication ("Sex Antagonism," by Walter Heape, F.R.S.). The author holds that this In no case does Mr. Heape give any picture of the birth-mark and the thing supposed to be represented by it, nor state that he has seen either the mark or a picture of it. In no case is the statement of the mother as to her having been "influenced" as described in the narration, tested or examined in any way. These and similar stories are related to-day, and such stories have been related from time immemorial. But they are always "hear-say." The witnesses and the facts are never carefully examined, and the degree of closeness of the agreement between the mark and its supposed cause are never really demonstrated. Nor has Telegony is the name given to the hypothesis that the offspring of a known sire sometimes inherit characters from a previous mate of their dam. The name means reproduction (Greek, gonos) influenced by a remote agent (Greek, tele = from afar). There is no question about "possibility" here. Such an "infection" of a dam by a previous mate is not improbable. According to Darwin "farmers in South Brazil are convinced that mares which have once borne mules, when subsequently put to horses, are extremely liable to produce colts striped like a mule." On the other hand, the Baron de Parana states that he has many relatives and friends who have large establishments for the rearing of mules where they obtain from 400 to 1000 mules in a year. In all these establishments, after two or three crossings of the mare and ass, the breeders cause the mare to be put to a horse; yet A celebrated case to which Darwin attached importance was that of Lord Morton's mare, reported to the Royal Society in 1820. This mare, after bearing a hybrid by a quagga (a striped equine related to the zebra) produced, to a black Arabian horse, three foals showing a number of stripes, and in one of them more stripes were present than in the quagga hybrid. This seems at first sight strong evidence in favour of "infection" of the mare by the early quagga mate. But it appears that stripes are frequently seen in high-caste Arab horses, and colts cross-bred from such and other breeds of horse sometimes present far more distinct bars across the legs and other zebra-like markings than were seen in the late offspring of Lord Morton's Arabian mare. The fact appears to be that all the living species of the horse family (horses, asses, quaggas, and zebras) are descended from an ancestry of "striped" equines, and are liable occasionally to "throw back" to their striped ancestry, more or less. Professor Cossar Ewart determined some years ago to submit the matter to direct experiment, and has related his results in a book ("The Penicuik Experiments," 1899). The South African equine called the quagga, which was that used by Lord Morton, having become extinct, Professor Ewart made use of a richly striped Burchell's zebra. Thirty mares put to this animal produced seventeen hybrids, and subsequently these mares, put to horse-stallions, produced twenty pure-bred foals. All the zebra hybrids were richly and very distinctly striped. Of the twenty later pure-bred horse-foals from the same mares three only presented stripe-like markings Breeders of dogs are (or were) even more thoroughly convinced of the fact of telegony than breeders of horses. But Sir Everett Millais, who devoted thirty years to the breeding of dogs and experiments on this question, states that he has never seen a case of telegony. And recent experiments of the most definite kind support his conclusion. Dalmatians, deerhounds, and retrievers have been used in these experiments. Many such experiments in telegony are accidentally or unwittingly made every year with dogs. An undesired crossing of two breeds takes place, but when subsequent pure breeding takes place no "telegonic" infection of the mother is observed. Cases believed to be due to telegony have on examination proved to be due to the carelessness of stablemen, Another curious case was that of a rickety spaniel puppy, which was exhibited a few years ago at the Zoological Society and believed by the exhibitor to owe its bandy legs to "telegonic" infection of the mother by a dachshund, with which she was supposed to have mated a year or more before being put to the father of the spaniel. Its true nature was at once recognized by the experts present, the bandy legs being those caused by "rickets," and not like those of the well-known dachshund breed. It appears that the explanations widely prevalent of many apparently strange things discussed in the preceding chapters, such as live toads buried in rocks, the water-finder's mystic rod, the coincidence of birth-marks and maternal impressions, and the inheritance of offspring from a previous mate of their dam, are hasty and unverified suppositions, which have never been properly tested, and that when the wonder-provoking statements made and the actual facts in question are properly and sufficiently examined, according to the rules of evidence and common sense, it is discovered that the assumption of occult or exceptional causes in explanation of such strange things are not justified, but that these strange things owe their strangeness in large part to the incorrect and incomplete observation of those who report them, and to that love of marvel and mystery which, like hope, springs eternal in the human breast. It is a remarkable proof of the reality of the belief The same thing has been observed in apples, melons, orchids, rhododendrons, grapes, maize, and peas, when one variety has been fertilized by the pollen of another, or when one species has been fertilized by the pollen of an allied but distinct species. The fruit in these cases (not simply the germ or young plant within it) has been found in some instances to have some of the colour, flavour, or shape and marking of the fertilizing variety or species blended or else mixed like a patchwork with that characteristic of the fertilized variety or species. The egg-producing or mother plant not merely has its ovules fertilized, but its tissues for some distance around are infected and made to take on—in parts of their living, growing substance—some of the quality of the fertilizing species. A similar thing occurs, though rarely, when cuttings of one plant are grafted on to another. The living tissue either of graft or of stock, and sometimes of both, is affected by the fusion with it of the tissue of the second plant united with it. And this appears to be a kind of "infection"—living particles passing from one to the other, and producing a mosaic or patchwork of the two kinds of living substance characteristic of each of the united plants. If an individual flower were to produce in a second year after its first fertilization and seed production a second set of ovules which could be fertilized by a kind of pollen differing from the first, it would not be surprising did that second set of ovules sometimes show characteristics due to the infection of the maternal tissues by the pollen used in the first year. But flowers In connexion with this matter it is to be noted that the sperm of one drone (her only mate) is retained in an internal sac or pouch, alive and active, in the queen bee, for some four or five years, and is used by her in successive seasons for fertilizing her eggs. Similarly it is recorded by the late Lord Avery that a queen ant kept by him for fourteen years, without access to a male ant, retained to the end of that period the power of producing eggs which developed into worker ants. He concluded that the sperm received fourteen years before by this queen from a male ant remained all this time alive and ready for Many strange and unwarranted beliefs persist because mankind prefers to accept an astonishing assertion as true rather than take the trouble to see whether it is so or not. Thus all antiquity and the later learned world wrangled about the very existence of Homer's city of Troy, until Schliemann said, "Don't talk! Dig!" and with childlike simplicity and directness uncovered ancient Troy. Thus the belief as to St. Swithin and his forty days of rain has been shown by the simple examination of the actual records of rainfall to be very far from the truth, since, though we often have a wet period in July and August, St. Swithin's Day is nearly as often free from rain in a wet season as the reverse. Forty days of rain very rarely indeed, in the South of England, have followed a wet St. Swithin's Day. The most amusing instance of the pricking of one of these bubbles of belief arose from the inquiry by some of the sham philosophers at the Court of King Charles II as to how it comes about that if a jar holding water be weighed, and then a live fish be placed therein without spilling any of the water, and the jar, with the fish and the water in it, be again weighed, there is found to be no increase in the observed weight. King Charles, it is said, made a bet that this was not so, and that there was nothing to explain. He referred the matter for decision to the newly founded "Royal Society for the Promotion of Natural Knowledge," which at other times he had asked to give him information as to the magic properties of the unicorn's horn and the cause of the movements of the recently imported "sensitive or humble plant." The believers in the marvellous disappearance of the weight |