Follicle hormones are isolated from the urine of pregnant individuals, or from preparations obtained from urine, by subjecting the starting material to steam distillation to remove volatile phenols, treating the residue with an alkaline agent, causing the solution to react with acylating agents, isolating the acylation product and saponifying it to yield the hormone.  When using urine itself the boiling with alkali is continued until ammonia is completely expelled.  The alkali used may be an alkali hydroxide, pyridine, or other compound of alkaline reaction.  The acylating agent may be p-toluene-sulphonic acid chloride dissolved in acetone, or benzoyl chloride, or other acid chloride or acid anhydride. Kieselguhr may be added to facilitate removal of the acylation product by filtration, or it may be extracted from the reaction mixture by means of ether.  Specification 401,205, [Group VI], is referred to.  The Specification as open to inspection under Sect. 91 refers to the use, as starting materials, of hormone-containing extracts from placenta or other organs, or from vegetable matter and to a process in which the step of boiling with an alkali is replaced by the step of dissolving in an organic solvent such as either or benzene and extraction of the solution with alkali hydroxide solutions whereby neutral constituents remain in the organic solvent; and contains an example relating to treatment of mares' urine wherein the acylating agent is p-toluenesulphonic acid chloride dissolved in benzene, the isolated acylation product is saponified by boiling with methanolic potassium hydroxide solution, the product is largely diluted with water, treated with sodium chloride, and extracted with ether, and the ether extract is washed successively with water, dilute hydrochloric acid and again with water and is extracted with successive quantities of aqueous potassium hydroxide, and the alkaline extract is acidified to yield crystals of the follicle hormone.  This subject-matter does not appear in the Specification as accepted.ALSO:Follicle hormones are isolated from the urine of pregnant individuals, or from preparations obtained from urine, by subjecting the starting material to steam distillation to remove volatile phenols, treating the residue with an alkaline agent, causing the solution to react with acylating agents, isolating the acylation product and saponifying it to yield the hormone.  When using urine itself the boiling with alkali is continued until ammonia is completely expelled.  The alkali used may be an alkali hydroxide, pyridine, or other compound of alkaline reaction, The acylating agent may be p-toluene-sulphonic acid chloride dissolved in acetone, or benzoyl chloride, or other acid chloride or acid anhydride. Kieselguhr may be added to facilitate removal of the acylation product by filtration, or it may be extracted from the reaction mixture by means of ether.  Specification 401,205 is referred to. The Specification as open to inspection under Sect. 91 refers to the use, as starting materials, of hormone-containing extracts from placenta or other organs, or from vegetable matter; and to a process in which the step of boiling with an alkali is replaced by the steps of dissolving in an organic solvent such as ether or benzene and extraction of the solution with alkali hydroxide solutions whereby neutral constituents remain in the organic solvent; and contains an example relating to treatment of mares' urine wherein the acylating agent is p-toluene-sulphonic acid chloride dissolved in benzene, the isolated acylation product is saponified by boiling with methanolic potassium hydroxide solution, the product is largely diluted with water, treated with sodium chloride, and extracted with ether, and the ether extract is washed successively with water, dilute hydrochloric acid and again with water and is extracted with successive quantities of aqueous potassium hydroxide, and the alkaline extract is acidified to yield crystals of the follicle hormone.  This subject-matter does not appear in the Specification as accepted.