The "B" vitamine is relatively easily absorbed by finely divided precipitates. We have already referred to the use of fuller's earth for this purpose by Seidell. This adsorptive power sometimes manifests itself in the treatment of plant extracts. A watery extract of alfalfa can be made to throw down its protein complex by diluting it to 40 per cent with alcohol. Osborne reports however that this process frequently removes the vitamine also which appears to be thrown down with the precipitated material. This adsorptive power therefore often appears as a difficulty in the handling of the substance as well as a means of extraction. We have used Osborne's method with alfalfa extracts and find the above result is not by any means invariable, for in some of our extracts we retained the greater part of the vitamine. Kaolin and ordinary charcoal are not very good adsorbents but the latter can be activated to serve this purpose. The elementary nature of the "B" vitamine remains a mystery. Extracts which contain it show the presence of nitrogen. Funk's earlier researches on yeast and rice polishings both yielded crystalline complexes which he analysed. His data on this subject follow: _A. The yeast complex_ Crystals melting at 233°C. consisting of: I. A complex melting at 229°C. and forming needles and prisms nearly insoluble in water and with the apparent formula of C_24H_19O_2N_5. II. A complex melting at 222°C. and soluble in water. Formula C_29H_23O_2N_5. III. Nicotinic acid melting at 235°C. C_6H_5O_2N. _B. The rice complex_ Crystals melting at 233°C. consisting of: I. A complex melting at 233°C. and with a formula of C_26H_20O_9N_4. II. Nicotinic acid melting at 235°C. C_6H_5O_2N. Funk held at the time that the possible nature of the compound was: HN | \ OC C_16H_18O_6 | / HN It was this idea that led him to call it an "amine." We are unable at present to report any nearer approach to the elementary analysis and all attempts at purification have shown a tendency to make the active substance either disappear entirely or else distribute itself over the several fractions instead of concentrating itself in one. Its basic nature seems to be well established by its behavior with phosphotungstic acid and its ready adsorption by carbons activated to take up basic substances. III. THE CHEMICAL PROPERTIES OF WATER-SOLUBLE "C"