231 



oells, thejr remain ineffective in others,- these cells do not' 

 react to thr-t kintl of stinmlue. Like so raany other phenomena. 

 v;e will'not he ahle to explain capacity and incapacity for re* 

 action in other "vray than hy the assumption of o specific nc^tuye 

 of the cells v/hich may he hased on structural conditions, oher»|t- 

 ical peculiarities, phenomena of tension and of movement in tl^e 

 cytoplasm and the cohesive and afthesive action of its molecules. 

 Uot only do cells of various plant spooies hehave differently;' 

 in regard to this capacity for reaction, >ut even the cells o^ 

 various organs and tissue forraa in the same species ar^d the 

 cells of different ages. In any case ve V7lll htxve to locate 

 the causes Of each reaction or non-ireaotion in the cytoplasm, 

 "BOfOh formr.tive pjfooess is oausoii hy the specific peculiarities 

 of the oj^oplasm, set freo or hrouf^ht about by a change in some 

 internal or external faoiors, 



(2T1> like everything that happens, tve can not picture to 



ourselves all forraative processes as othervrise than casually 

 conditions - which holds good for the variously changing 

 pathological formative processes aa vrell as for the normal 

 ones vhich In corresponding organs In the sp^me plant species 

 41wnys lead to well-knor/n structures. Each formative Pro- 

 cess is caused by the specific quality of the cytoplasm and 

 by the sum of all the active factors, which bring about the 

 separate processes, of formation, The mixed kingdom or nor- 

 mal and abnormal forms is thus far a vells-ordered one; the 

 opposite is Inconceivable, Each separate process takes 

 place as a matter of neoessiry and is the only on^ possible 

 under the conditions just then In control. The enormous 

 diversity among p.bnotmal forms can not lead us astray here,- 

 just as for the locomotive, when travelling over 4 '^^^J. 

 branched network of rails, there is only one way ipossible, 

 which is determined by the sum of all the effective fao- 

 tora,- in this case, by the placing of the switches, 



If, in comparing normal and abnormal tissue tor^^t^J 

 speak of "arrested developments", of a "tendency'! to aixr 

 ferentiation, which "exceeds" the normal degree ar^d Kina ox 

 tissue differentiation and so forth, these are al^ ^^JPJ®"^ 

 sions which are of course meant only figuratively rn d n.-ve 

 been chosen because of their vividness. In the firm oausj^i 

 system represented by the course of developrant JJT ^'^.y'^* 

 ganisra, there is no reom for special "tendencies" of Jf® 

 cells and tissues toward any pa ticular method of devexopT 

 ment, V7here, hovrever, no tendency exists, re ©an also 

 speak only figuratively of any "arrestment". There is no 

 "normal" and ^'abnormal", no "tendency" and no "arrestment 

 for the organism which does not "strive" for any apf JJ^-»- 

 ("normal") method of development, but.QS a natural no ay 

 without will power, is formed just as the sum of "che exxe j- 

 nal and internal factors may determine absolutely. ^«^J°® 

 introduction of such terras is necessary in our work since 

 we can obtain clearness, and be understood only by a com- 

 parison of the diverse ferws and process© s among tnemseAveo 

 and by th0 establishing of a norm, by which we attempt 

 to standardize all. 



After these introduotory remarks, it will be o^' *^^^^}j,^ 

 that which follows, to ascertain and analyse so far ^f P^ff,*^-*"^ 

 the factors active in abnormal tissue formation; ^®^!!^''-\^^ot 

 ther have to consider the reaction to stimulation , pj. ^^^J2^^"^ 

 formative processes, from general points of view and then i*»" 

 ally test the capacity for reaction in various plants and pianT 

 tissues to response to definite stimuli. 



