CnAi>. IV] TROnCAL DISTRICTS CONSTANTLY MOIST 333 



with justice, included it among the protective devices. Opinions however 

 'ilTcr as to tlic nature of the danger to be guarded against. Wiesncr 



V[G. 175. Lrowiie.i hyLriiU-i with pLni.li.iU )uunij twigs. Botanic garden at Buitenzorg. 

 From a photograph by M. Treub. 



jconsiders the danger to be too strong ilhimination ; Potter, too great heat; 

 jStahh mechanical damage by hcav\' rain ; Haberlandt, several factors 

 icting simultaneously. Decisive experiments have not yet been made. 



