_Experiment No. 16._--On February 28, 1906, a white rabbit weighing 581.2 grams was injected subcutaneously at 10.35 a.m. with a concentrated aqueous extract of 83 grams of fresh _Astragalus mollissimus_ collected in September, 1905, and preserved with chloroform. The temperature before injection was 102.1°F. At 1.40 p.m. the animal was dull; at 3.12 p.m. the temperature registered 99.8°F. The animal died during the night. The post-mortem examination was negative. Stomach pale; heart relaxed save left ventricle, which seemed contracted; dural vessels of the brain dilated; kidneys perhaps normal. No microscopical examination.
_Experiment No. 17._--February 28, 1906, at 10.25 a.m., a guinea pig weighing 496 grams was injected subcutaneously with a concentrated aqueous extract of 83 grams of the fresh _Astragalus mollissimus_ preserved in chloroform water. At 1.40 p.m. there was muscular twitching. The animal was dull and could be easily turned on his back. The hind legs began to show weakness. At 1.50 p.m. the hind legs were almost completely paralyzed and the animal could be easily turned on his back. Muscles of the limbs twitched and semen was expelled. Animal died at 2.15 p.m.
Post-mortem showed dural vessels of cord and brain full of blood. Stomach pinker than normal: mesenteric vessels dilated. Heart almost empty of blood. Kidneys congested.
=SUMMARY OF FEEDING EXPERIMENTS ON RABBITS.=
These experiments indicate that an acute form of poisoning may be induced by feeding concentrated aqueous extracts of _Astragalus mollissimus_ and _Aragallus lamberti_ from Hugo, Colo., and Imperial, Nebr., to rabbits, and that if the extract is given in smaller and repeated doses a more prolonged or chronic condition may follow.
The rabbits showing the chronic effects of these plants exhibit symptoms which have a marked parallelism with those reported as occurring in larger herbivora (horses and cattle) on the range when locoed; that is, the loss of appetite (Experiment No. 9), the emaciation and loss in weight (Experiment No. 9), the dullness and stupor, with more or less anesthesia (Experiment No. 7), the disturbance in the visual function (Experiment No. 9), and the mental symptoms (Experiment No. 6). The occasional abortion compares with what has been observed in larger animals. The dried _Astragalus mollissimus_ and _Aragallus lamberti_ still retained their poisonous properties, as we were able to kill with aqueous extracts of the dried plants made in the laboratory under the proper conditions.