DESERT VEGETATION OF AMERICA 



159 



Parish's catalogue of Salton Sink plants. Here, I have taken 

 only the xerophytes, regarding trees and shrubs as Fanero- 

 phytes, "semi-shrubs" as Chamaephytes, " perennial herbs" as 

 Hemicryptophytes and Geophytes and " annual herbs" as Thero- 

 phytes. 



The four biological spectra resulting are given in the table. 

 To them is added the spectrum for Death Valley quoted from 

 Raunkiaer (1908) who made it after Coville's catalogue of Death 

 Valley plants, and further the "normal spectrum" is put down 

 after Raunkiaer. This is the biological spectrum for 400 species 

 taken at random from a list of the plants of the whole earth; 

 it should accordingly be the biological spectrum of the whole 

 earth. 



1 Five percent marsh-plants are not entered, accordingly the percentages 

 given are a little too low. 



2 One percent marsh-plants are not entered. 



From the table the following conclusions can be drawn: 



1. The plains at Akron are characterized by Hemicryptophytes 

 which constitute more than half of all the species. Chamae- 

 phytes are also common, at least compared with the normal 

 spectrum. Therophytes keep to the level of the normal spectrum. 



2. Tooele has still many Hemicryptophytes, but next to them 

 come the Chamaephytes, which are indeed very conspicuous in 

 Utah. There are two Fanerophytes only (Sarcobatus and Juni/>- 

 erus), and Therophytes are as in Akron. 



3. In Tucson the Hemicryptophytes have decreased under 

 the percentage of the normal spectrum so that this region is 



