atter, giving no colour-reaction with
iodine, is termed achroocellulose; the former reacts, and is therefore
termed erythrocellulose. The former is easily separated from its
opalescent solution. It has the empirical composition of cellulose. In
the soluble form it resembles glycogen. The achroocellulose is isolated
in the form of horny or agglomerated masses. It appears to be resolved
by ultimate hydrolysis into dextrose and mannose.

SECTION V. FURFUROIDS, i.e. PENTOSANES AND FURFURAL-YIELDING
CONSTITUENTS GENERALLY

(1) ~Reactions of the Carbohydrates with Hydrogen Peroxide.~

C. F. CROSS, E. J. BEVAN, and CLAUD SMITH (J. Chem. Soc., 1898, 463).

(2) ~Action of Hydrogen Peroxide on Carbohydrates in the Presence of
Ferrous Salts.~

R. S. MORRELL and J. M. CROFTS (J. Chem. Soc., 1899, 786).

(3) ~Oxidation of Furfuraldehyde by Hydrogen Peroxide.~

C. F. CROSS, E. J. BEVAN, and T. HEIBERG (J. Ch. Soc., 1899, 747).

(4) EINWIRKUNG VON WASSERSTOFFHYPEROXID AUF UNGESAeTTIGTE
KOHLENWASSERSTOFFE.

C. F. CROSS, E. J. BEVAN, and T. HEIBERG (Berl. Ber., 1900, 2015).

~ACTION OF HYDROGEN PEROXIDE ON UNSATURATED HYDROCARBONS.~

The above series of researches grew out of the observations incidental
to the use of the peroxide on an oxidising agent in investigating the
hydrolysed furfuroids (102). Certain remarkable observations had
previously been made by H. J. H. Fenton (Ch. Soc. J., 1894, 899; 1895,
774; 1896, 546) on the oxidation of tartaric acid by the peroxide,
acting in presence of ferrous salts, the --CHOH--CHOH-- residue losing
H_{2} with production of the unsaturated group, --OH.C=C.OH--. These
investigations have subsequently been considerably developed and
generalised by Fenton, but as the results have no immediate bearing on
our main subject we must refer readers to the J. Chem. Soc., 1896-1900.

From the mode of action diagnosed by Fenton it was to be expected that
the CHOH groups of the carbohydrates would be oxidised to CO groups, and
it has been established by the above investigations (1) and (2) that the
particular group to be so affected in the hexoses is that contiguous to
the typical

|
--CO

group. There results, therefore, a dicarbonyl derivative ('osone'),
which reacts directly with 2 mol. phenyl hydrazine in the cold to form
an osazone. This was directly established for glucose, laevulose,
galactose, and arabinose (2). While this is the main result, the general
st