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Different stages 

 in the division 

 of the protozoan 



Popular Science Monthly 



Mr. George E. Stone, of Berkeley, California, 

 has hit upon the idea of applying this principle 

 to make clear the complex subject of life and the 

 methods by which plants and animals are born, 

 live and die. With the assistance of Dr. J. A. 

 Long, Professor of Embryology- in the Universit}^ 

 of California, a film has been prepared which not 

 only surpasses anything that has hitherto been 

 attempted in showing the blossoming of flowers, 

 but which is of immense scientific importance as 

 well. No doubt other scientific men have had the 

 same idea. But for lack of a suitable apparatus 

 they were unable to photograph the minute life 

 which is seen only through the microscope. This, 

 Mr. Stone has invented. Some of the remarkable 

 films which he has obtained are reproduced in 

 connection with this article. 



Simple Cells Merely Split in Two 

 The simplest plant or animal is that which 

 consists of but one cell. Hence his film starts its 

 photographic lesson in "How Life Begins" by 

 showing a swarming mass of protozoans — simplest 

 of all animals, because their bodies consist of but 

 a single cell each. A protozoan reproduces its 

 own kind by the simple process of splitting itself 

 up into two parts. That fact the film drives home 

 very clearh^ A protozoan, highly magnified, is 

 obser\-ed to constrict and divide in the middle. 

 Each of the halves thus formed at once becomes 

 a new one-cell creature. And each of these new 

 creatures, in turn, splits up into new cells, until 

 thev become so numerous that at last one realizes 



89 



In making motion pictures of microscopic life, Mr. 

 Stone used the electric arc. The camera was 

 driven by an electric motor controlled by the foot 



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It was a three 

 weeks' task to take 

 this strip of fJm 



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New protozoans 

 resulting from a 

 division of an or- 

 iginal protozoan 



