Uses.--The bark of this tree has a wide reputation in India as a tonic and febrifuge. The inner layer of the bark possesses astringent and bitter properties much like quinine. Ainslie states that it is used in India to tan hides and therapeutically where an astringent is required. O'Shaughnessy experimented with it in the hospital of the Medical College of Calcutta and reported good tonic and antipyretic effects. In 1870, according to Dymock, Broughton analyzed the fresh bark and reported that the bitter taste was due to _esculin_, which after drying and coming in contact with decomposing organic matter is transformed into the almost tasteless _esculetin_. Naylor studied the bark at a later period, and attributed the bitterness to an alkaloid that he named _hymenodictyonine_. This substance exists in the form of a gelatinous mass, cream-colored, very hygroscopic. An ethereal solution, carefully evaporated, deposits it in the form of crystals. Its empirical form is C_23_H_40_N_2_; it is probably volatile and is notable for its lack of oxygen. It differs from _quinoidine_ in that it is inactive (?) and that in combination with platinum it retains less of this metal than does quinoidine. It differs from _paricine_ in its proportion of hydrogen, and from _berberine_ in containing more carbon. In the presence of sulphuric acid its solution assumes a yellow color, changing to wine-red and then to dark red. Naylor extracted another principle which he found combined with the alkaloid in a soda precipitate of the latter; it is a product of the decomposition of a glucose, the formula of which is C_25_H_49_O_7_. This compound remains insoluble when the alkaloid is treated with ether. Repeated boiling in alcohol renders it colorless. It is bitter, soluble in alcohol and dilute acids; insoluble in ether and chloroform. Reaction, neutral. Botanical Description.--A large tree, with leaves opposite, oval, entire, acute, downy. Petioles long, flat above, with 2 stipules. Flowers axillary, in compound verticillate racemes. Calyx adherent, with 5 promptly deciduous teeth which leave a scar that also disappears. Corolla much longer than the calyx, funnel-form, the limb 5-cleft. Stamens 5, inserted near the middle of the tube. Filaments rudimentary. Anthers 2-celled. Style longer than the corolla. Stigma globose. Seed-vessel rather rough, ovoid, flattened, of 2 compartments, where are inserted numerous seeds, imbricated, circular, encircled by an entire wing. Habitat.--Angat and the woods of San Mateo. Blooms in August. (P. Blanco states further that this tree grows to a height of about 3 yards in Angat and that it exhales a strong odor resembling that of vinegar at times, and again like that of tobacco.) _Oldenlandia corymbosa_, L. (_O. biflora_, Lam.; _O. ramosa_, Roxb.; _O. herbacea_ and _serabrida_, DC.; _O. burmaniana_, Mig.) Nom. Vulg.--Doubtful.