THE AMERICAN BOTANIST. 61 



root varying from three to six inches in thickness and descend- 

 ing to a depth of from four to nine feet. 



Those not accustomed to desert Hfe and the way plants 

 manage to exist on an arid plain and in an arid atmosphere 

 would certainly be surprised at the immense roots some of these 

 especially adapted plants have. The sage brush can hardly be 

 said to represent even an average in the matter of root devel- 

 opment ; for many plants as the "soap weed'' (Yucca) and the 

 bush morning glory (Ipomea) have truly enormous roots.. 

 This plant is also provided with very rudimentary leaves and 

 a corky layer of bark encasing the root as well as the stem 

 above ground. These modifications give little chance for trans- 

 piration to take place. Thus it circumvents all attempts 

 of the thirsty sun to steal the life-moisture so hard to secure 

 from an apparently moistureless soil. 



Again we find that this plant has a bitter acrid taste from 

 which it derives the name wormwood. Animals are forewarn- 

 ed of this taste by the peculiar aromatic odor the plant pos- 

 sesses, which thus protecting itself from the attacks of herbi- 

 vorous animals. In time when the ground is covered to the 

 depth of several inches with snow when other articles 

 of food are scarce it is eaten regardless of taste and has been 

 reported to cause the death of domestic animals. We find 

 in this plant certain medicinal qualities which are supposed to 

 give it value as a tonic for numerous ailments. Like others 

 of the wild things of nature it tends to recede as civilization 

 advances for one never finds it in cultivated ground. 



The genus to which this plant belongs is very interesting 

 botanically as thirty-nine species are reported from Colorado 

 alone. The variations which are now considered of suflficient 

 importance to give specific rank are many and quite difficult 

 to make out. 



One who has never seen the sage brush should have (if 

 this description is graphic enough) the following mental pic- 

 ture : It is a plant covering large areas of the plains very thick- 



