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Show POULTRY I THE LAWS OF HERIDITY. By C. S. Gorline. ' J The riddle of inheritance has never been guessed and today is as much of an enigma as it was in the days of Buffon, Semper and Lamark. It remains as complete a mystery as the vital spark of life and is one of Nature's baffling unexplained, and un-cxplainablc un-cxplainablc secrets. Hypothesis after af-ter hypothesis has 'been proposed by the most gifted scientists the world has produced, each to be discarded in time under the crucial test of experiment, ex-periment, and the problem of hcridi-ty hcridi-ty remains unsolved. Such a little thing such a wonderland of simplicity simpli-city in the beginning of c.cll life yet leading to such tremendous consequences con-sequences in the end. Just a simple little cell in the embryo it may be of plant or bird or fish or mammal it matters not, but it is endowed with the vital spark and grows and develops and carries within itself the power to reproduce the characteristics character-istics of remote as well as immediate ancestry dtown to the minutest details. de-tails. This is hctidity, the most wonderful trait of organic life. A germ cell imbued with the spark of life takes on a wall, divides and subdivides sub-divides and forms its mass of cells into tendon and nerve and muscle and arranges each in accord with predetermined plan with unerring accuracy ac-curacy so that every living thing reproduces re-produces its own kind and never by any mischance any other kind. The germ cell of a bird will never develop into any thing but a bird and the germ cell of a horse will never develop deve-lop into a cow. Not only will this simple cell reproduce its own species, spec-ies, but wil reproduce even the latent characteristics of remote individuals of that species. How and why docs it do this? Shall we ever knojv? Some of the laws that govern have been madle known. Perhaps others may become known until at last Nature's Na-ture's secret shall become our own. We know that the ovum is a cell alle to reproduce its like, which during dur-ing development gives rise not only to divergent cells of the organism, but to other cells like itself, and that M . ...... this ovarian cell contains material particles : une kind :na ccrrc-pond ccrrc-pond to each of the hcriditary. characteristics char-acteristics of the species. iTit j Naturalists have summarized thv. I ' " known laws of hcridity under differ- y ent heads, which may be stated as follows:" direct hcridity, rcvcrsional hcridity, collateral hcridity, co-equal hcridity, pre-marital hcridity, pre-natal hcridity and initial hcridity. Direct hcridity is that form in which the child inherits the likeness and characteristics of its parents ana the law is summarized in the words: like will produce like. The offspring may exhibit the peculiarities of both parents, or if one parent has very strongly marked characteristics, both sexes of the offspring may resemble that parent. If the parents arc of equally strong blood-lines, their peculiarities pe-culiarities will generally be reproduced repro-duced in opposite sexes, that is, the females will resemble the sire and the males the' dam. Remarkable vigor vig-or in one parent, mated to inconsequent inconse-quent strength in the other should stamp the traits of the stronger on both sexes of the progeny, and while this is generally true as to general characteristics, it is not uncommon in such cases to note a faithful portrayal por-trayal in both exes of the progeny of a striking likeness to the weaker parent. Whether breeding ifor. exhibition ex-hibition or for utility, this fact should be constantly born in mind; in such cases, a close adherence to known ' blood-lines must -be followed in selecting se-lecting breeders from such a mating. Reversal hcridity is that form in which the child resembles its grand- parent, some times termed atavism. The law may be stated as follows: Peculiarities of rcvcrsional hcridity make their appearance in alternate generations. Students of hcridity arc agreed that there can be no explanation ex-planation of individual traits without ,taking into c deration this law three times out of ten. The traits of the grandfather are reproduced in the grandson, and those of the grandmother in the granddaughter. If we are trying to breed out some undesirable characteristic, it may disappear dis-appear for generations, but in time, may rc-appear in some alternate generation gen-eration with great force andi per sfsterlce. Careful selection and rigid restriction may eradicate the fault, or perpetuate a centgener value, as the case may be. Collateral hcridity is that' form in which the progeny inherits the traits of lineal antecedents out of the di- f vUb rcct Imc' as a "' may stronsiy fj" resemble a cousin, an uncle or some I distant relation. The law may be t stated thus: Peculiarities of collater al hcridity arc due to close inbreeding inbreed-ing or may result from a direct out-cross. out-cross. This is a most curious display dis-play of seemingly accidental inhcrit-Iancc inhcrit-Iancc and we doubt that the phenomena phenome-na will ever be observed) except as the effect of the causes mentioned. Co-equal hcridity refers to the law of sex distribution, by which an excessive ex-cessive numibcr of cither male or female fe-male may not be reproduced. This is the least understood of any law of inheritance and the mystery as to how Nature preserves in substantial substan-tial equality the proportionate number num-ber of each sex is unsolved and the secret is her own. Every experienced exper-ienced breeder is aware that in some years an excessive number of mules arc produced to be followed by other years in which the females arc in excess, and yet in the 'general average, aver-age, 'the sexes will be about equal, that is, in equal proportion. Prc-nvatcrial hcridity is that form of inheritance which often makes its appearance in subsequent matings wherein the progeny may bear a striking; cscmblance to tin mal I of the first mating. The law may be summarized) as follows: Prcma-tcrial Prcma-tcrial hcridity is due to the force of magnetic impression, or telcgony. As an illustration, suppose a child of a second or third marriage resembles the husband of a previous marriage. This presupposes that a tchild was born of the previous marriage. The blood ' of the mother circulates through the child while in embryo, and fromi the child through the mother, moth-er, charged with the magnetic life fluid. This life fluid is composed of the magnetic impregnating ethers transmitted by the sire to the cmbyro and circulating through every vein and capillary of the mother, become a part of her physical being. The central life forces of the sire, transmitted trans-mitted through the child, become incorporated in the organism of the mother, and the hcridity traits of that sire may be transmitted to offspring off-spring by a subsequent marriage 1 Pre-natal hcridity is the result of 'surrounding influences upon the mother during pregnancy. The effect is chiefly shown in birth-marks, or other peculiarities, owing to severe fright, a shock or other influences that stamp their impression upon the cmbyro. Initial hcridity is a form that has but recently been considered as playing play-ing an important part in shaping or forming the characteristics of individual indi-vidual development. This law affects the inheritance of man as well as the breeding of livcistock. It may be summarized as follows: Initial hcridity hcr-idity is the result of intelligent selection. se-lection. If we breed vicious animals, wc may not expect kind dispositions in the progeny. If wc select breeding breed-ing stock of high intelligence and of gentle disposition, we may expect to develop these traits in the progeny. o |