158 OVE PAULSEN 



in Copenhagen, partly by aid of floras) and the letter repre- 

 senting the growth-form was written at the plant's name: F 

 denotes Fanerophyte, Ch Chamaephy.te, H Hemicryptophyte, 

 G Geophyte, Th Therophyte. When each plant has got its 

 letter, the types are counted up and their percentage is cal- 

 culated. 



The following plant-lists have been made use of: 



1. For the plains at Akron, Colorado, the lists published by 

 H. L. Shantz for the different plant-associations. He gives 79 

 species (Cryptogams excluded) which is, as he remarks him- 

 self, not a complete enumeration, but they will, I hope, consti- 

 tute a fair representation as to growth-forms of the plants of the 

 region. 



2. The lists given by Kearney, Briggs, Shantz, McLane and 

 Piemeisel for the different associations in the Tooele Valley, 

 Utah. The lists include 116 species and are likely to be fairly 

 exhaustive, as the authors have visited the place several times 

 at different seasons. 



3. Spalding's exhaustive list of Plants of the Desert Labora- 

 tory domain at Tucson, Arizona. Spalding gives (p. 104) sta- 

 tistics of what he calls " vegetation forms" of plants from dif- 

 ferent habitats, and from his table I have taken the numerals 

 given for TumamocHill and for the Mesa-like mountain slopes and 

 added them together. Thus I have not taken into account the 

 plants from the flood plain or from the irrigation ditches or 

 introduced species. This I have done because the numerals 

 must be comparable with those from Akron and Tooele where 

 hygrophytes are not considered. Of Spalding's "vegetation 

 forms" I have identified trees, shrubs, dwarf -shrubs and woody 

 twiners with Fanerophytes, half shrubs with Chamaephytes, 

 perennial and biennial herbs with Hemicryptophytes (and 

 Geophytes) and annual herbs with Therophytes. This identi- 

 fication may not be right in all cases — especially with regard to 

 Fanerophytes and Chamaephytes — but still I think I could hardly 

 come nearer the truth than in this way, having no Arizona flora 

 and only a scanty amount of herbarium material from that state. 



4. In a similar manner I have used the analysis annexed to 



