The Unity of the Organism 



ology by Haeckel, have been exceedingly useful, and their 

 usefulness depends largely on the fact that the root ontos 

 refers to a living being, an organism as a totality, so that 

 coupled with the term genesis, the reference is to the entire 

 cycle of the being, and not merely to some particular stage 

 of that cycle, as is the case with the term embryogeny. The 

 word embryon, the back-bone of embryogeny, embryology, 

 and the like, means, as the Greek dictionaries tell us, "the 

 fruit of the womb before birth." It is synonymous with the 

 Latin foetus. In other words, the center of reference of all 

 terms containing the root being primarily to one stage, and 

 that a very immature one, of a higher organism, it may 

 be held with considerable justice to be inapplicable to the 

 development of such lowly creatures as the protozoa. But 

 to define ontogeny so as to exclude reference to the develop- 

 ment of the protozoan or any other organism is not only 

 utterly unjustifiable, but deserves unqualified scientific con- 

 demnation, because, as we have seen, it gives persons not 

 well informed and so not in position to be on their guard 

 against being misled, a narrow and false conception about 

 organic development. The full mischievousness of this sort 

 of limitation is seen only by looking a little more into details. 



Development of Stentor as an Example of Protozoan 

 Ontogent/ 



The familiar "trumpet animalcule," Stentor, found in fresh 

 water ponds almost everywhere and figured in many books, 

 will serve our purpose well. Numerous zoologists have made 

 this animal the object of their studies, one of which only, by 

 H. P. Johnson, will be drawn upon. The case of Stentor is 

 the more instructive in that its mode of propagation is 

 chiefly if not entirely that of "simple cell division" to use a 

 phraseology that is pleasing to simple elementalism. 



Before entering upon an account of the development of 



