466 MANUAL OF POISONOUS PLANTS 



poisoning. Many die, but most recover. Prof. Chesnut, in his Principal Poison- 

 ous Plants of the United States, says : 



The percentage of fatal cases in cattle which have eaten this and other larkspurs 

 is said to be small. A rough estimate by a cattleman places it at about 20 per cent for 

 one species of the group, when the animals are not properly treated, and 5 per cent other- 

 wise. This is probably a low estimate, however, for in a case of poisoning from D. Men- 

 ziesii that occurred in Montana in May, 1897, and was reported by Dr. E. V. Wilcox, 

 nearly 600 sheep were affected, 250 of which died. 



Dr. Wilcox says in regard to D. glaucum: 



The tall larkspur appears not to be eaten by sheep. All cases of poisoning from this 

 plant observed in Montana during this year and previous years have been among cattle. 

 As already indicated, sheep are not driven to the mountain ranges until about the middle 

 of July, and at this season the tall larkspur is altogether too large and coarse for their 

 consumption. It is well known, on the other hand, that cattle will feed on much coarser 

 forage than sheep, and at the same time they are allowed to run on the high ranges in 

 the early spring. In Montana the light green tufts of leaves of the tall larkspur first 

 become conspicuous about the last of April or the first of May, and the flowers begin to 

 open about the middle of June. This fact is significant for the reason that light falls 

 of snow often occur in the larkspur belt as late as the first week in June, and, since there is 

 then no other verdure in sight, the uncovered portion of the larkspur is in a high degree 

 tempting to stock, all the more because it is succulent. The danger is increased by the 

 fact that at the time of snow falls cattle seek the shelter of creeks where the larkspur is 

 more abundant and most advanced in growth. At this period, moreover, the leaves are, 

 as we can testify from personal observation, very bitter, and they are probably then more 

 poisonous than at any other stage of growth. The older ones, as is also the case with 

 the blue larkspur, are not so bitter. The plant is recognized by cattlemen as dangerous 

 to cattle from May until about the middle of June. Mr. Yard Cockrell informs us that 

 on his range in the lower basin of the Gallatin it is the sole duty of one man during this 

 period to keep his cattle away from the broken mountainous regions where this larkspur 

 abounds. 



The symptoms are described as follows : 



In general, the animals affected manifest symptoms similar to those produced by overdoses of 

 aconite. The first signs of poisoning are usually a general stiffness and irregularity of gait. There 

 is often a pronounced straddling of the hind legs in walking. These symptoms increase 

 in severity until locomotion becomes difficult or impossible, and the animal finally falls to 

 the ground. It usually falls and gets on its feet again a number of times, the muscular 

 movements becoming more and more irregular and incoordinated. At the same time the skin 

 is very sensitive to touch, and the muscles of the sides and legs soon begin to quiver spas- 

 modically. This a very characteristic symptom, being usually exhibited for several hours. 

 The function of the special senses is seldom impaired, the animal being apparently able to 

 hear and see as well and as correctly as under conditions of health. Although a slight 

 increase in the quantity of saliva is to be noticed in some cases, this symptom is never 

 so pronounced as in cases of poisoning by death camas. During the later stages of 

 poisoning the animal is usually attacked with violent convulsions, in one of which it finally 

 dies. In this respect, also, the symptoms differ distinctly from those of death camas poison- 

 ing, which is usually quite without spasms. The digestive functions seem not to be af- 

 fected by larkspur poisoning The temperature is lowered slightly during the first stages, 

 in one instance having been as low as 97. During the later stages the pulse becomes very 

 frequent and the breathing rapid and shallow. The cerebral symptoms are simply those of 

 excitement, and the appetite seems not to be lost until shortly before death. 



In regard to D. bicolor, the symptoms observed from experiments are 

 k-scribed by the same author as follows : 



Summing up the results of these experiments, we find that the most prominent, easily 

 observable symptoms were a stimulation of the respiration and a brain symptom manifested 

 by dizziness or a rhythmical movement of the head. As it was not the object of the ex- 

 periment to determine the symptoms of poisoning, these having been already secured by Dr. 

 Wilcox, no special effort was made to determine the pulse rate, but it was to be noted that 

 in experiment 2, which was as nearly fatal as any, the heart action was extremely rapid 

 and weak. None of the experiments proved fatal and no results were obtained on which 



