284 MEMOIRS OF THE NEW YORK BOTANICAL GARDEN. 



der Botanik, p. 396. 1892). Thus he says :" Fa^st man die hier her- 

 vorgehobenen Charaktere der etiolirten Pflanzenlheile richtig auf, so 

 gelangt man zu einer ganz anderen Erklarung des Etiolements als wie 

 sie bisher versucht worden ist." And in his discussion of his own in- 

 terpretation of the matter the following statement is made: " Fiir 

 alle Organe aber wo Ueberlangerung im Dunkeln sich einstellt, ist 

 diese aber auch wieder in einen anderen Sinne eine vortheilhafte 

 Anpassung, denn sie ist hier ein fiir gewohnliche unfehlbares Hiilfs- 

 mittel,um den wachsenden lichtbediirftigen Pflanzentheil schliesslich 

 doch ans Licht zu bringen." Meanwhile Godlewsky's extensive 

 discussion of the subject had previously appeared and his conclu- 

 sions seemed to be confirmed by the observations of the author and 

 those of F. Darwin in 1896, and Pfeffer '^' has adopted this explana- 

 tion of the matter in his recent text-book. 



Thus he says: "In richtiger Erwagung der Sachlage kann es 

 nicht zweifelhaft sein, dass sich bei dem Etiolement in erster Linie 

 um eine Reizwirkung des Lichtes aber nicht um einen durch Nahr- 

 ungsmangel verursachten Erfolg handelt." It is to be noted that 

 Palladine saw in the altered forms of etiolated plants the lack of the 

 influence of light in the promotion of transpiration, and the develop- 

 ment of the surfaces which ordinarily enlarge the capacity of the 

 plant for throwing off watery vapor, an explanation that has been 

 found to be insufficient to account for the phenomena in question 

 (1890-1893). There remains to be mentioned the proposal of Noll 

 to use the term "etiolation" to designate adaptational elongations 

 which take place for the purpose of carrying foliar or reproductive 

 organs up into their proper media and to exposures of optimum in- 

 tensity, and to recognize among other forms of etiolation " water- 

 etiolation " by which the stems of aquatics are elongated to bring the 

 leaves and flowers to the surface, " darkness-etiolations " to include 

 the phenomena forming the subject of the investigations to which this 

 memoir is chiefly devoted, and "reproductive-etiolation" to denote 

 the sudden elongation that ensues in propagative and reproductive 

 branches (1902). " Green-etiolates" had already been suggested by 

 Bonnier in this connection to designate the excessively elongated 

 shoots of plants grown in continuous electrical illumination (1895). 



''''Pfeffer. Pflanzenphysiologie, 2 : 114. 1901. 



