1^ The Unity of tJie Organism 



case he was looking at the organism primarily from the 

 morphological standpoint while in the other he viewed it 

 more from the physiological side. 



In the mere matter of extent and deliberateness of re- 

 liance- upon the principle of organic wholeness, nothing in 

 recent biological literature with which I am acquainted is 

 more impressive than what one finds in The Cell in Develop- 

 ment and Inheritance, by E. B. Wilson. The organism as 

 a whole or some obvious substitute therefor is appealed to 

 on no less than seventeen pages of this book, these appeals 

 being scattered all through from the beginning to the end 

 of the volume. So far as such views of this distinguished 

 cytologist have been embodied in a single sentence, the fol- 

 lowing in his essay. The Mosaic Theory of Dezrelopment 

 seem to contain them : "The only real unity is that of the 

 entire organism, and as long as its cells remain in con- 

 tinuity they are to be regarded, not as morphological indi- 

 viduals, but as specialized centers of action into which 

 the living body resolves itself, and by means of which the 

 physiological division of labor is effected." ^ 



The most recent and in several ways the most significant 

 presentation of the organismal theory in relation to cells 

 comes from another embryologist, F. R. Lillie. It is worth 

 noting that this time the chief grounds of the presentation 

 are experimental embryology, whereas with Whitman they 

 are embryology unaided by experiment. In 1906 Doctor 

 Lillie published an unusually interesting research on the de- 

 velopment of a species of worm, Chaefopterus pergamen- 

 taccus. The kernel of the results was a confirmation and 

 extension of previous observations by himself and several 

 other investigators that under certain conditions the embryo 

 of some species of annelid worms may progress some dis- 

 tance on the develo})inental course before cellular or even 

 nuclear multiplication takes place. The author's summary 

 of facts may be given in his own words : "In general the 



