Abstract: 1.The writers attempted to clearfy the confusion of the names of Datura crude drugs in China.Basing on the cultivated plants from seeds collected from various places of this country,the following plants were identified,namely:(1) Datura tatula L.,(2)Datura stramonium L.,(3)Datura inermis L.,(4)Datura metel L.f.alba,and(5)Datura innoxia Mill.The last named has been mistaken for Datura metel L.for a long period,is specially pointed out. 2.The pharmacognostical studies are made in details on histology,powder form,and the pollen grain structures. In additiort to the descriptions,fourteen drawings are prepared,and we hope this paper may be helpful to pharmacognocists for identifying both the plants as well as commercial crude drugs.