POISONS AND THEIR ANTIDOTES. 



I. THE PURPLE LOCO WEED. II. THE WHITE LOCO WEED. III. POISONlNa 



BY LOCO PLANTS. IV. SYMPTOMS OF LOCO POISONING IN HORSES. V. 



SYMPTOMS OF LOCO POISONING IN CATTLE. VI. SYMPTOMS OF LOCO POI- 

 SONING IN SHEEP. VII. TREATMENT OF LOCOED ANIMALS. VIII. SUMMARY. 



I. The Purple Loco Weed. 



Astragalus mollissimus, popularly known as the "purple loco" or the 

 "woolly loco," sometimes as the "Texas loco," or the "true loco/' is the 

 plant that in the past has been considered as the more probable cause of 

 loco poisoning. This is sometimes known as the "stemmed loco plant," 



A PLANT OF THE PURPLE LOCO WEED. 



because it has true stems, while the white loco weed is stemless. The for- 

 mer is a perennial plant growing in patches on adobe soil, in depressions 

 rather than in elevated situations. It rarely grows in the abundance which 

 is characteristic of some of the other so-called "loco plants," but it may 

 cover several acres. Under favorable circumstances where a plant grows 

 for several years it may become, perhaps, a foot in height and possibly 2 

 feet in diameter. The flowers are a very deep, purple and the pods short, 

 black, and thick. The leaflets are ovate or elliptical and very densely cov- 

 ered with hairs, from which the plant gets its common name of "woolly 



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