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Show 90 THE PERPE'l'UATION OF LlVI:XG BEINGS, This tendency to variation is less marked in that. mode of propagation which takes place asexual I y; it is in that mode that the minor characters .of animal and vegetable structures are most completely preserved. Still, it will happen sometimes, that t11c gardener, when he has planted a cuttino- of some favourite plant, will find, contrary to his e~(pectation, that the slip grows up a little different from the primitive stock-that it produces flowers of a differ - ent colour or m·<t l\·. e , oI · some" cl. ev1·a t"I On 1· n one wav or another. This is what is called the 'sporting' of pl;nts. In animals the phenomena of asexual propagation are so obscure, that at present we cannot be said to know much about them; but if we turn to that mode of perpetuation which results from the sexual process then we find variation a perfectly constant occurrence 7 to a certain extent; and, indeed, I think that a certai~ amount of variation from the primitive stock is the ~ecessary r~sult of the method of sexual propagation Itself; for, Inasmuch as the thing propagated proceeds from two organisms of different sexes and different. make.s and temperaments' and as tile off's pn.n g· 1. s to ~e either of one sex or the other, it is quite clear that It cannot be au exact diagonal of the two, or it would be of no sex at all; it cannot be an exact intermediate for~ between that of each of its parents-it must deviate to one side or the other. You do not find that the male follows the precise type of the male parent, n~r. does the female always inherit the precise char.a ctenstics of the mother' -there is 'a l ways a pro-portiOn of the female character in the male offspring7 HEREDITARY TRANS:\£ISSION AND VARI.:\..TIO~. 91 ancl of the male character in the female offspring. That must be quite plain to all of you who have looked at all attentively on your own children or those of your neighbours; you will have noticed how very often it may happen that the son shall exhibit the n1aterna\ type of character, or the daughter possess the characteristics of the father's fa1nily. 'rhcre are all sorts of intermixtures and intermediate conditions between the two, where complexion, or beauty, or fifty other different peculiarities belonging to either side of the house, are reproduced in other 1nembers of the same family. Indeed, it is sometimes to be remarked in this kind of variation, that the variety belongs, strictly spea1<ing, to neither of the immediate parents; you will see a child in a family who is not like either its father or its mother; but some old person who knew its grandfather or grandmother, or, it may be, an uncle, or, perhaps, even a more distant re1ati,·e, will see a great similarity between the child and one of these. In this way it constantly happens that the characteristic of some previous member of the family comes out and is reproduced and recognized in the n1ost unexpected manner. But apart fron1 that matter of general experience, there are some cases which put that curious mixture in a very clear light. You are aware that the offspring of the Ass and the Horse, or rather of the he-Ass and the Mare, is what is called a Mule; and, on the other hand, the offspring of the Stallion and the she-Ass is what is called a Hinny. It is a very rare thing in this country to see a Hinny. I never saw one myself; but they have |