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other direction, we may resolve the cells into molecules, 

 and the molecules into atoms, and down, down, deeper, 

 until, if possible, we reach the ultimate monad the 

 ptyeOr) aSicupera, amid the properties or endowments mani- 

 festly in the very nature of the ultimate fractional . parts of 

 matter, but the mystery of life is unsolved, and beyond 

 life is Infinity. 



In seeking for the physiological causes of heredity, it 

 will thus be seen that they are bound up with the mysteries 

 of generation, and in either case we have reached the 

 ultimate revelation of science when we regard the fusion 

 of two simple cells as resulting in the production of a 

 compound cell the " embryonic vesicle " within which 

 are enshrined the mysteries of reproduction and heredity. 



All the elements and functions of the human body are 

 subject to heredity internal as well as external its 

 peculiarities, diseases, and even acquired modifications. 



The likeness between parents and children is a matter of 

 daily observation, not only as to form, feature, and expres- 

 sion, but also as regards the peculiarities of the limbs, 

 trunk, head, nails, hair, skin, complexion, gait, voice, 

 temperament, etc. That family likenesses will continue for 

 ages may readily be seen from family portraits when they 

 have been preserved for many generations ; and, although 

 seemingly lost in one generation, they will assuredly become 

 manifest in a succeeding one. The phenomena of the 

 external structure those affecting the features and outward 

 configuration of the body although comparatively more 

 common and of less engrossing interest, are not, neverthe- 

 less, the least instructive. The facts concerning the 

 hereditary characteristics have, as has already been stated, 

 been recognised from time immemorial by all peoples and 



