HEATH FAMILY. 71 



LOCO WEED OR MILK VETCH Astragalus spp. 



The resemblance between these plants and the stem- 

 less Loco Weeds is marked. They may, however, usually 

 be distinguished by the presence of leafy stems, but al- 

 ways, as stated above, by the absence of any spur at the 

 tip of the keel in the blossoms. Of the seventeen species 

 listed by Rydberg, a number are undoubtedly responsible 

 for loco disease and are as poisonous as the Stemless 

 Loco Weeds. One species, Astragalus moUissimus Torr-, 

 has caused great losses in parts of the western United 

 States. Chesnut says the damage done to the live-stock 

 business by this weed is immense. The State of Color- 

 ado paid out nearly $200,000 in bounties between 1881 

 and 1885, to check its ravages. 



Barium salts have been suspected as the toxic sub- 

 stance of the Loco Weeds. 



HEATH FAMILY Ericaceae. 



LAURELS Kabnia spp. 



Several poisonous species of Kalmia are found in Can- 

 ada and the United States, growing in dry places and in 

 Poisonin bos s - Their leathery leaves, and, in fact, all 

 by Laurels parts of the plants, contain andromedodextrin, 

 a substance stated by Chesnut to be more 

 poisonous than strychnin, though it is almost the reverse 

 in its action. Grouse and deer appear to be immune to 

 its effects. When they have fed on it, however, their 

 flesh is said to be poisonous to human beings and to other 

 animals. It is reported that people have been poisoned 

 by eating honey extracted from the flowers. 



