ritter: astragalus mollissimus. 199 



observed last summer being larvae in the stem, insect galls, fun- 

 gous diseases, and leaf miners. 



Some of the theories proposed to account for the loco disease in 

 stock caused by these plants are : 



(1) The weed absorbs the juices of the alimentary tract, causes it 



to dry up and exert pressure enough to kill the animals. 



(2) Overfeeding on loco weeds. 



(3) A fungous parasite on loco weeds, Claviceps. 



(4) The indigestible character of the plant. 



(5) Malnutrition and malassimilation. 



(6) Starvation. 



(7) Irritation by hairs. 



(8) Disturbance to digestion. 



(9) Poison developed in digestion. 



(10) Not due to loco weeds, but accompanying them. 



(11) Alkaloids. 



(12) Some poisonous principle not yet isolated. 



(13) Barium salts. 



The effects of the disease on animals have been described as 

 various. However all agree on a few, as here given by Marsh 



('09). 



Slow staggering gait. 



Rough coat. 



Staring look. 



Emaciation. 



Lack of muscular coordination. 



Extreme nervousness, shown in shying, rearing, etc. ^ 



To which might be added : 



Lack of sensitiveness. 

 Hallucination. 



A horse walking under a telephone wire several feet above its 

 head will lower its head to get under, or when stepping over a 

 stick or a rut in the road will lift its feet very high. The coat of 

 the animal becomes rough, the eyes have a glassy look; there may 

 be, in cattle, a sac of serous fluid under the chin. After the habit 

 of eating loco weeds is formed the animals will hunt for them, and 

 reject other food in preference to them. When locoed they are 

 very hard to manage, and it is almost impossible to back a locoed 

 horse. One cow is reported, when shut up to keep her away from 

 the loco weed after she had the habit, to have run against a stone 

 wall so hard as to kill herself. Starting to walk across a pasture, 

 affected animals keep going until they come against some ob- 

 struction. A horse will walk through a barb-wire fence, not 



