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SCIENCE. 



[N. S. Vol. II. No. 34. 



constricts itself in the middle and finally 

 cuts itself in two. The original amoeba is 

 no more ; in its place there are two. Thus 

 nearly at the bottom of the scale of life are 

 manifested all of the fundamental features, 

 the living substance moves itself, takes 

 nourishment, digests it and changes non- 

 living into living substance-and increases in 

 size ; it seems to feel and to avoid the disa- 

 greeable and choose the agreeable and 

 finally it performs the miracle of reproduc- 

 ing its kind, of giving out its life and sub- 

 stance to form other beings, its offspring. 



It is the belief of many biologists that the 

 larger and complex forms even up to man 

 himself may be considered an aggregation 

 of structural elements originally more or less 

 like the amtsba just described; but instead 

 of each member of the colony, each individ- 

 ual itself carrj'ing on all the processes of 

 life independently as with the ama'ba, there 

 is a division of labor. Some move, some 

 digest, some feel, think and choose, some 

 give rise to new beings, all change lifeless 

 matter into their own living substance. 



The processes and phenomena by which 

 a new individual is produced are included 

 under the comprehensive term, Embryol- 

 ogy- 

 All organisms, great or small, are but de- 

 velopments of minute germs budded off by 

 the parent or parents, and the way in which 

 these minute beginnings develop into per- 

 fect forms like their parents can only be 

 followed by the aid of a microscope. In- 

 deed, in no field of biology has the micro- 

 scope done such signal service in revealing 

 the processes of life. 



The method of the production of a new 

 being with the ama?ba, as we have just seen, 

 is for the parent to give itself entire to its 

 ofispring — the parent ceasing to be in pro- 

 ducing its ofispring. With some other 

 lowly forms a part of the body of the par- 

 ent buds out, grows and finally falls off" as 

 an independent organism, or remains con- 



nected with the parent to form a colony. 

 In the plant world a familiar example of a 

 colony is represented by the cactus that 

 the children call ' Old Hen and Chickens.' 



In the higher animals, however, where 

 specialization has been carried to its ex- 

 treme limit, some myriads of cells forming 

 the body are set apart to produce motion, 

 others digest food, still others think and 

 feel, while comparatively few, the germ 

 cells are destined for the continuation of 

 the race. In the higher and highest forms 

 especially, all observation goes to show that 

 the life energy, not satisfied with the mere 

 vitalization of matter and a dead level of 

 excellence, is aiming at perpetual ascent, 

 greater mastery over matter and its phys- 

 ical forces. For the more certain attain- 

 ment of this end, the production of offspring 

 is no longer possible for one individual; 

 two whollj^ separate individuals must join, 

 each contributing its share of the living 

 matter which is to develop into a new be- 

 ing. In this way the accumulated acquire- 

 ments of two are united with the conse- 

 quent increase in the tendencies and im- 

 pulses for modification, and nearly double 

 the protection for the offspring. Thus in 

 striking contrast with the amceba, where 

 the single parent gives all of itself to form 

 offspring, and in so doing disappears and 

 loses its individuality, the higher forms, 

 while two must unite to form the offspring, 

 the parents remain and retain their individ- 

 ualitj' and the abilitj^ to produce still other 

 offspring. The process by which this is ac- 

 complished may be traced step by step with 

 the microscope. A germ cell of the father 

 and one of the mother fuse together, and 

 from this new procreative cell, formed by 

 the fusion of two with all their possibilities 

 combined, the new individual arises. This 

 certain knowledge is the result of the pro- 

 found investigation of the last few years 

 and shows the literalness of the scriptural 

 statement, ' they shall be one flesh.' 



