THE IX ADEQUACY OE THE CELL-THEORY. II3 



On the botanical side, Sachs has maintained since 1865 (" Experi- 

 mental-Physiologie ") that protoplasm is an '■'■organized body" (cf. 

 Lectures on Physiology, 1887, p. 206-7). While Briicke contended 

 for organization within the cell, and remained true to the cell-theory 

 of all higher organization, Sachs, Goebel and some other botanists 

 early challenged the doctrine of cell-hegemony. Sachs briefly indi- 

 cates his standpoint in the following words : 



" To many, the cell is always an independent living being, which 

 sometimes exists for itself alone, and sometimes ' becomes joined with ' 

 others — millions of its like, in order to form a cell-colony, or, as 

 Haeckel has named it for the plant particularly, a cell-republic. To 

 others again, to whom the author of this book also belongs, cell- 

 formation is a phenomenon very general, it is true, in organic life, but 

 still only of secondary sigtiijicancc ; at all events, it is merely one of 

 the numerous expressions of the formative forces which reside in all 

 matter, in the highest degree, however, in organic substance." (Lect- 

 ures, etc., p. 73.) 



Briicke's great merit consists in this, that he taught us the 

 necessity of assuming structure as the basis of vital phenomena, 

 in spite of the negative testimony of our imperfect microscopes. 

 That function presupposes structure is now an accepted axiom, 

 and we need only extend Briicke's method of reasoning, from 

 the tissue-cell to the egg-cell, in order to see that there is no 

 escape from the conclusion that the whole course of develop- 

 mental phenomena must be referred to organization of some 

 sort. Dcvclopniciit, no less titan other vital phenomena, is a 

 function of organization. 



Nageli followed the same method of reasoning when he con- 

 cluded that the organism was, in a certain sense, " vorgebildet " 

 in the germ-cell (Beitrage zur wiss. Botanik, Heft II. i860). 

 This point of \-iew is well expressed in his classical work, the 

 " Theorie dcr Abstammungslehre," where he says: " Organisms 

 differ from one another as egg-cells no less than in the adult 

 state. The species is contained in the egg of the hen as com- 

 pletely as in the hen, and the hen's lig^^ differs from the frog's 

 Gigg just as widely as the hen from the frog." 



While all will admit that the organization of the ^gg is such 

 as to predetermine the organism, few will be prepared to admit 

 that tJie adult onrani.zation is identical in its individuality 



