220 EXPERIMENT STATION RECORD. 



"sugar" loses water when heated in vacuo to 100 to 106° C, becomes 

 hard and brittle, and after 4 hours has the composition C^H^Ou. 

 YVheu heated for 24 hours the composition becomes C,;H 10 O r ,. The 

 conditions under which tartaric acid is oxidized by atmospheric oxygen 

 are present during the growth of the plant, and the formation of this 

 "sugar" may be of importance in connection with the production of 

 carbohydrates in the vegetable kingdom. — W. H. KEUG. 



Melibiose, A.Batj (Ghem.Ztg., 21 (1897), No. 21,1). ISO).— To obtain 

 the material for the investigation melitriose was inverted with acid or 

 fermented in a 10 per cent sterilized solution with surface yeast. The 



products obtained by fermentation showed (ri),,= + 126.88 h 137.50 



at 17.5° C. in a 2 dm. tube, while those obtained by inversion gave 

 (a) D = -f- 137.32 or -f 139.34 for ash-free substance. The redueing power 

 of melibiose, which was formerly given as 83 per cent of that of mal- 

 tose, was found to be 90 to 93 per cent, was higher the more dilute the 

 solution, and increased as the time of boiling was extended. Melibiose 

 can only be inverted by melibiase. and not by invertin (euinvertase). 

 It is inverted by hydrochloric, sulphuric, and oxalic acids, while lactic, 

 tartaric, and citric acids have no action. Sacch«romyces apiculatus, 

 Schizosaceharomyces Pombe Lindner, and Saccharomyces Logos van 

 Laer do not act on melibiose; the latter two slowly split melitriose into 

 ^-fructose and melibiose. — W. h. keug. 



The formation of mannan in Amorphophallus konjak, M. Tsuk- 

 AMOTO (Imperial Univ., Coll. Agr., Toliio, Bui. 2, p. 400; abs.in Chem. 

 Centhl., 1897, I. No. 18, p. 933). — The leaves of Amorphophallus Jconjak 

 contain little starch and considerable mucilage, which was found to be 

 an anhydrid of maunose. This fact makes it probable that the mannan 

 play the role of starch in the leaves, although it is not certain that man- 

 nose is the first product of assimilation. Mannose was found in the 

 stems. — W. II. KRUG. 



The action of diastase on starch, A. E. Ling and J. L. Baker 

 (Jour. Chem. Soc. [London], 71 (1807), Xo.414,p.508).— The limited action 

 of diastase on starch at 70° C. gives the following unfermen table prod- 

 ucts: rt-nialtodextiin^'^H^Ori, identical with the maltodextrin of Brown 

 and Morris, but having (o) D =180° and reducing power R=32.81; 

 /i-maltodextrin, C^II^O?, identical with Prior's acchroodextrin 3, hav- 

 ing («) D =171.6° and E—43. From the unfermeutable residue of that 

 fraction, which Lintuer designated isomaltose, a substance was isolated 

 which lias the composition C^H^-On and is isomeric with maltose. It 

 has (a-) D =156° and B = 62.5, and may be the simple dextrin Ci 2 H 20 O 1( ), 

 H 2 0. The results indicate that the hydrolysis of starch by diastase 

 yields a series of successive maltodextrins of lower molecular weight 

 and rotatory power and higher reducing power. — W. H. krttg. 



The quantitative separation of the cellulose-like carbohydrates 

 in plants, W. Hoffmeister (Landw. Vers. Stat., 48 (1897), No. 6, pp. 

 401-411, fig. 1). — The hemicellulose, cellulose, and lignin were deter, 

 mined in a number of feeding stuffs by the following method: The 



