78 STOCK-POISONING PLANTS OF MONTANA. 



antidote could be based; hence no experiments were made in that line. 

 Neither were the experiments numerous enough to deduce any posi- 

 tive results as to the comparative toxicity of the various parts. By 

 inspection of the various experiments, however, it will at once be seen 

 that the most satisfactory ones in this regard were the fourth and 

 sixth, in which the water solution of extracts was fed. The equivalent 

 of 44 grams of the root of the flowering plant was fed to a rather 

 small rabliit, 26 ounces in weight, without causing anj^ appreciable 

 effect, while in experiment 4, where the roots from nonflowering plants 

 were used, about half the quantity, 21i grams, produced some of the 

 characteristic symptoms of the plant, although fed to a rabbit weigh- 

 ing 63 ounces — over twice as much as the other. It seems probable, 

 therefore, that the older root is little, if at all, toxic. The fact that 

 the alcoholic extract from 2i grams of the j^oung root was without 

 effect on a 55.-ounce rabbit when injected h3"podermically is not signif- 

 icant. The experiments show that the root of the young plant is poi- 

 sonous and tend to show that those of the mature plant are not. It is 

 possible, however, that advanced age may alter the chemical combina- 

 tion of the alkaloid and render it insoluble in water without affecting 

 its toxic character. Other more powerful solvents might have 

 extracted the poison, but the limitations of time and the multiplicity 

 of other experiments precluded further investigation. 



The extracts for experiments 1, 2, and 8 were prepared in the same 

 way. A comparison of the results is interesting, inasmuch as it tends 

 to explain the apparently anomalous results referred to above, which 

 were obtained when Dr. Nelson fed a verj^ considerable amount of 

 a related species of larkspur to sheep without noting an}^ marked 

 symptoms. The extract from 20 grams of leaves taken from partly 

 wilted flowering plants produced only a slight uneasiness when fed to 

 a 26-ounce rabbit, while very positive results were obtained in the 

 other experiments where a much smaller amount of the extract was 

 used. The weight of the rabbit in the latter case was somewhat less, 

 but the difference was not at all sufficient to account for the difference 

 in effect. That there is a positive difference is also evident from a few 

 observations made on the comparative taste of the leaves at the two 

 stages of growth. Those from j^oung plants gathered at the same 

 time as that from which PI. V was taken had a decidedly bitter taste, 

 and those from flowering plants gathered later were distinctly acid and 

 rather agreeable. Our experiments show that there is a slight amount 

 of poison in the leaves. Experiments 7 and 9 show that the stalks of 

 flowering plants, and especially the flowers, are poisonous. It is very 

 frequently asserted that the fatal effects of larkspur on stock are only 

 produced when the root has been eaten. One of us. Dr. Wilcox, has, 

 however, already shown that it is extremely difficult in most cases for 

 animals to pull up the roots, and our experiments with the young 



