31 



The liver exhibited acute parenchymatous hepatitis with passive con- 

 gestion. The kidneys exhibited low-grade parenchymatous nephritis. 

 Myocardium, acute myositis. 



THE ACTIVE PRINCIPLE OF ASCLEPIAS MEXICANA 



Several species of Asclepias which are physiologically active have 

 been examined chemically, and, from the work done by various experi- 

 menters on those investigated, the compounds to which the physiologi- 

 cal activity of the plant may be ascribed apparently varies considerably. 

 Glucosides have been found in several species, which act on the animal 

 organism as an emetic. In another species (syriaca) a crystalline 

 resinous substance was found which acted as an anodyne and cathartic. 

 Quackenbush reports finding a crystalline glucoside in Asclepias tuber- 

 om and Asclepias cornuti. March, Clawson, Couch, and Eggleston 

 (U. S. D. A., Bui. 800) have recently reported preliminary experiments 

 on Asclepias yalioides, a species closely related to A. Mexicana, in which 

 they found evidence of the presence of toxic compounds having nar- 

 cotic properties and also those producing a spasmodic type of intoxica- 

 tion. The active principles were not isolated, but experiments on small 

 animals indicated the presence of toxic material in successive extracts 

 of the dry plant, and gave some idea of the solubility relations of these 

 materials. They found that petroleum ether removed no active mate- 

 rial, but that benzol extracted substances which were toxic and pro- 

 duced effects in test animals similar to those observed in poisoning of 

 slieep by the plant. Ether and chloroform extracts from the material 

 already treated with benzol and petroleum ether also were toxic, indi- 

 cating the possible presence of more than one activ'e principle. Other 

 solvents failed to remove toxic matter from the residue. Evidence of 

 the presence of a minute quantity of alkaloids was obtained ; volatile 

 poisons and saponins were not found. Alcohol alone was found to 

 extract all of the toxic material, a part of which was soluble in water 

 producing narcosis, and the part insoluble in water producing poisoning 

 with symptoms typical of range poisoning. 



A portion of the material used in our feeding experiments was 

 examined, and results were obtained which were in some ways similar 

 to those reported on Asclepias galioides. 



A small quantity of the plant was extracted successively with sol- 

 vents and the amounts extracted by each were as follows : 



Benzol 10.55% 



Ether 0.64% 



Chloroform 0.70% 



Ethyl acetate 2.68% 



Alcohol 0.46% 



Each of the residues from these extractions were administered to 

 guinea pigs by mouth in amounts corresponding in each case to five 

 grams of the dry plant, and all appeared to be nontoxic, except the 

 benzol extract. Thus benzol is capable of removing all of the toxic 

 substances. No reactions were noted in the cases of the materials 

 extracted by the other solvents, the animals appearing normal. 



Another small portion of the dry powder was studied by extracting 

 with dilute acid and testing with the general alkaloidal reagents. With 

 each reagent used, indication was obtained of the presence of alka- 



