BIOLOGICAL PAPERS. 195 



If we take the view that loco weed is non-poisonous, and that the 

 peculiar symptoms which follow the ingestion of the weed in large 

 quantities for a long-continued period be due to a malnutrition or a 

 disturbed condition of the digestive tract, we naturally look to a pos- 

 sible mechanical disturbance brought about by one or more of the 

 elements making up the structure of the leaf. This we find in in- 

 numerable unicellular hairs which cause the characteristic pubescence 

 of the leaf. These hairs seem to constitute about one-third of the 

 weight and over one-half of the bulk of the powder. 



We append below the ' bibliography relating to this interesting 

 subject : 

 Loco Weed. 



Description of: L. H. Pammel, professor botany, Iowa Agricultural College. 

 The Vis Meclieatrix, June, 1891, p. 40 (journal of the Iowa State Medical 

 Society). The article contains figure of rattle-box (Crotalaria sagittalis). 

 WooLLy Loco Weed; Stemless Loco Weed; Rattle-box. 



Description of: V. K. Chestnut, U. S. Dept. of Agriculture, division of 

 botany. Principal Poisonous Plants of the United States. Bulletin No. 

 20, 1898, p. 29. 



Fig. 12. — Woolly loco weed (Astragalus mollissimus). 

 " 13. — Stemless loco weed ( Argallus lambertii). 

 " 14. — Rattle-box (Crotalaria sagittalis). 

 Description of: V. K. Chestnut, assistant botanist, U. S. Dept. of Agricul- 

 ture. Thirty Poisonous Plants of the United States. Farmers' Bulletin, 

 No. 86, 1898, p. 14. 



Fig. 8. — Woolly loco weed (Astragalus mollissimus). 

 " 9. — Stemless loco weed (Argallus lambertii). 

 " 10.— Rattle-box (Crotalaria sagittalis). 

 White Loco Weed. 



Description of: V. K. Chestnut and E. V. Wilcox, department of botany, U. 

 S. Dept. of Agriculture. The Stock-poisoning Plants of Montana. Bulle- 

 tin No. 36, 1901, p. 86. 



Plate 9. — White loco weed (Argallus spicatus) in flower. 

 " 10.— White loco weed (Argallus spicatus) in fruit. 

 Silvery Loco Weed ; Purple Loco Weed. 



Description of: V. K. Chestnut and E. V. Wilcox, division of botany, U. S. 

 Dept. of Agriculture. The Stock-poisoning Plants of Montana. Bulletin 

 No. 36, 1901, pp. 99, 100. 



Plate 11. — Silvery loco weed (Argallus splendens). 

 " 12. — Purple loco weed (Argallus besseye). 

 " 13. — Purple loco weed (Argallus lagopus). 

 Loco, or Crazy Weed. 



Description of : J. U. Lloyd, Cincinnati, Ohio. The Eclectic Medical 

 Journal, Oct., 1893, Art. XCI. 



Loco Weed. 



Description of: Dr. F. B. Power and J. Cambier. The Pharmaceutical 

 Rundschau, 1889, p. 134. 

 Fig. — Crotalaria sagittalis. 



