The filtrate B (p. 20) from which gallic acid was precipitated by sulphuric acid in four fractions was saved to examine for sugar. To remove gallic acid completely, and other vegetable matter, it was shaken out several times with ether, and was kept at a low temperature with salt and ice for a long time. It was left standing for several weeks, during which time more brown matter separated out and was filtered off. The filtrate was evaporated to a small bulk, cooled, and filtered from crystals of potassium sulphate. The filtrate was evaporated to dryness, the residue taken up in water and filtered through bone-black. Addition of alcohol caused complete precipitation of potassium sulphate. The solution then gave the above mentioned characteristic tests for rhamnose. All attempts to get the osazone of the sugar by the method of Fischer[38] failed, probably on account of the small quantity of the sugar present. The plant, it will be remembered, was originally extracted with ether in which rhamnose is practically insoluble. The above described tests, however, can leave no doubt as to the identity of the sugar. Additional evidence that the sugar is rhamnose was obtained by a method described by Maquenne[39] as follows: "The production of methyl furfurol in the dehydration of isodulcite furnishes a very simple means of characterizing this sugar in mixtures which contain it; it is sufficient, for example, to distil 50 gm. of quercitron wood with as much sulphuric acid and about 150 gm. of water, then to rectify the liquid obtained in order to get several drops of the crude furfurol, which on addition of alcohol and concentrated sulphuric acid gives immediately the green coloration characteristic of methyl furfurol. This procedure is applicable to extracts as well as to entire plants, and has the advantage that it does not require the separation of isodulcite, the crystallization of which is often very slow and at times impossible when it is mixed with other very soluble substances." The experiment was tried with the crude ether extract of the plant according to the directions of Maquenne, and the green color with alcohol and sulphuric acid was obtained from the thicker oily portion of the distillate. This test can be made with hydrochloric acid[40] as well as with sulphuric. Therefore the color test was tried with the ester mixture prepared in one of the early experiments by boiling the original plant material with hydrochloric acid and alcohol. Methyl furfurol was found here also, this method indeed giving better results than that of Maquenne.