42 THE PHYSICAL BASIS OF LIFE 



formed components follow this order ; tliey do not create 



What then constitutes the fundamental or primary 

 organization of the egg '? No one is yet able to answer. The 

 embryologist, the cytologist, the physiologist and the bio- 

 chemist — all alike have thus far only skirted the outer- 

 most rim of the problem. We can not predict how far the 

 cytologist of the future may be able to penetrate within 

 it; but it would seem that sooner or later his way will 

 finally be blocked by inherent limitations of the micro- 

 scope determined by the wave-length of light. If we are 

 ever to find our way into the innermost arcanum of the 

 cell all the resources not only of cytology but also of 

 experimental embryology, genetics, biophysics and bio- 

 chemistry must be marshaled. The problem of organiza- 

 tion has as yet barely been touched by purely physico- 

 chemical analysis. Genetics, it is true, has of late made 

 remarkable advances tow^ard the study of the nuclear 

 organization but leaves unsolved the problem of the ' ' or- 

 ganism as a whole." Experimental embryology has eluci- 

 dated the phenomena of development by many important 

 discoveries,"" but at the same time has emphasized our 

 failure thus far to solve the central problem — it was in- 

 deed from this source, that Driesch, a distinguished pio- 

 neer in this field, drew the facts on which he based liis 

 famous argument against the machine-theory of develop- 

 ment and attempted to set up in its place a new philoso- 

 phy of vitalism. This argument was originally based on 

 his own remarkable discovery that a single cell (blasto- 

 mere) isolated from its fellows at the 2-cell or 4-cell stage 

 of development, is able to produce a perfect dwarf larva 

 that is a precise miniature of the normal one from a com- 

 plete egg. The argument was re-enforced by the demon- 

 stration nearly at the same time, by the brothers Hertwig 



