128 ANIMAL LIFE IN DESERTS 



In the same way it is stated that Pallas' Sand- 

 grouse {Syrrhaptes paradoxus) feeds very largely on 

 a salt-loving desert Chenopodiaceous plant, Agrio- 

 phyllum, in Central Asia. 



Such close connection between the animal or 

 bird and the plant on which it lives is obviously 

 a potential danger to it. A severe drought, a fire, 

 a flood, or some other natural cataclysm, such as 

 is not uncommon in deserts, may exterminate bird 

 and plant together, at any rate over a part of their 

 range. 



The plants which are most important as fodder 

 for domestic animals in deserts belong to those 

 perennials which live above ground at all seasons. 

 Sheep in the more arid parts of AustraUa depend 

 largely upon salt-loving succulents (Zygophyllaceae 

 and Salsolacese), particularly during periods of 

 drought, and in the drier parts of the southern 

 United States plants of the Cactus family are used 

 in the same manner. 



I can recall only one instance of animals depen- 

 dent upon plants for water and not for food, and 

 that was observed in the hill country of Palestine, 

 which is certainly not desert, and barely falls within 

 our definition of semi-desert. However, in the 

 rainless summer, the season at which this obser- 

 vation was made, the country is extremely arid, 

 and the observation is, I think, suggestive enough 

 to warrant inclusion here. AH over the hills of 

 Judaea and Samaria there grows a genus of stout 

 thistles (Echinops) with spiny globular heads. These 

 flower in June and July when water is very scarce. 



