273 



characters; others are to be found in size, in odor, perhaps also 

 the natural doubling of flowers might be recognized in this man- 

 ner, as this involves a mere transformation of parts and no 

 essential structural differences, although here we are running 

 pretty close to morphological characters; I am not sure, how- 

 ever, that it would be best to rigidly exclude certain of these. 

 The difficulty will be to limit the use of the term to some defi- 

 nite set or sets of characters. If we enforce merely relative per- 

 manency we shall all have different views as to what this implies. 

 The whole subject of the limitation of the various ranks in 

 classification is one which botanists will do well to consider and 

 the pages of the BULLETI^Mvill be open to communications on 

 the topic. By the presentation of different views we might be 

 enabled to reach some valuable conclusions to guide us in sub- 

 sequent work. The difficulty in restricting the use of '* form *' is 

 met with in variety, in species, in genus, and, indeed, in every 

 term of our system* Let us have a discussion of the matter, if 

 r nothing else, in order to ascertain just what thoughts are in 

 the minds of botanists of the present generation, for all must 

 have thought more or less about it. Then those of us who meet 

 in Indianapolis will be in a position to talk it over in all its aspects. 



fo 



I 



M 



bility of changing a published name, however, if a supposed spe- 

 cies or variety was to be reduced to a form, for I presume that 

 the trouble that this would give the future student would out- 

 weigh the slight advantage of a descriptive adjective; so I should 

 be for forma Jonesii of his supposed white harebell if it had 

 been published as Campanula Jonesii or C rottindi folia, van 



Jon 

 Jon< 



make no difference either to 



Ibifli 



N. L. Britton. 



The Mandioca. 



By Thomas Morong. 



In an economic point of view the Mandioca or Manioc is one 

 of the most important agricultural productions both of Brazil and 

 Paraguay. It takes the place of wheat in the northern conti- 



