22 BULLETIN 947, IT. S. DEPARTMENT OF AGRICULTURE. 



11. Experiments witli the juice. — (a) The juice is very toxic and 

 small amounts of it fed daily for an extended period produce spewing 

 cases. It was shown that all of the dugaldin might be precipitated 

 from the juice, leaving a liquid which is not acutely toxic. Sheep 

 460 received on separate days three doses of 650 mils each of juice 

 which had been precipitated with tannic acid and filtered. This 

 produced no effect. Inasmuch as 250 mils of the untreated juice 

 were sufficient to kill in a short time, it is evident that the tannin had 

 removed the toxin. 



(6) It was desired to see whether juice precipitated with tannic acid 

 would cause the spewing cases. Accordingly three sheep, Nos. 463, 

 473, and 501, were given from June 25 to August 23, inclusive, daily 

 doses of juice from 2 pounds of fresh leaves from which the dugaldin 

 had been removed by precipitation with tannic acid. As a precau- 

 tion against tannic-acid poisoning, the precipitant was added only 

 in slight excess to the juice and, after filtering off the precipitated 

 glucosidal tannate, the excess of tannic acid was removed by neu- 

 tralizing the solution with ammonia when the tannic acid precipi- 

 tated as a calcium compound. At the end of the experiment each 

 sheep had received the detoxicated juice from 118 pounds of fresh 

 H. Jioopesii radical leaves. None developed spewing symptoms and 

 all survived. 



(c) Part of the tannic compound of the glucosid produced in these 

 experiments was dried and fed to Sheep 482 in 2-gram doses daily 

 (1£ pounds green leaves) for 31 days and in 4-gram doses for 25 days 

 without producing any definite effect. 



(d) A quantity of moist glucosidal tannate from 49.5 pounds of 

 radical leaves was warmed with water and magnesium oxid in an 

 attempt to decompose the compound and liberate the dugaldin. 

 This mixture was fed in divided doses to Sheep 503 twice daily for 

 24 days. The animal did not become seriously sick, but the urea 

 excretion was markedly diminished, which indicated that the glu- 

 cosid was behig partly absorbed. It was later found impossible to 

 regenerate the glucosid quantitatively from its tannic acid compound, 

 and it is believed that in these cases the larger part of it was excreted 

 without having ever been absorbed from the alimentary tract. 



(e) A quantity of the juice was treated with animal charcoal and 

 after seven days had lost its bitterness and color; 500 mils of this 

 juice (about 2 lethal doses of untreated juice) were drenched into 

 Sheep 539 without producing any effect. 



12. Toxicity experiments with dugaldin. — A number of animals were 

 given doses of a solution of dugaldin in order to test the toxicity of 

 that glucosid. The details of some representative cases are pub- 

 lished in Table 2. 



