Abstract: Solid compositions based on plants, capable of being converted to a dry and porous galenic form (lyophilized or equivalent form) which is undivided or powdered. Said dry and porous galenic form comprises a solid composition II consisting ofa solid composition I composed of:(A) one or more of the plants' active principles included in a homogeneous suspension of fresh or dry plants obtained by (a) cleaning and/or drying of the plant or part of the plant, (b) cryocomminution at a temperature below 0.degree. C. until a particle size of less than about 100 .mu.