210 
SUMMARY OF CURRENT RESEARCHES RELATING TO 
with the common hemp, in order to ascertain the relation between the 
nature of the soil and the colour, habit, weight, and general facies of 
the plant. The colour was found to be most intense, the height greatest, 
and the dry weight most, when a manure containing a large proportion of 
nitrogen was used. When no nitrogen was present the colour was very 
light. When no phosphate was present in the manure the hemp seemed 
to be considerably taller and of a deeper colour than when no nitrogen 
was present ; hut when no potash was present the heiglit was very much 
reduced. The absence of lime did not seriously affect the height of the 
plant. 
Wave-growth of Corydalis sempervirens.* — Mr. T. Meehan de- 
scribes what he terms a recoil in the wave-growth in Corydalis semper- 
virens. The author has pointed out that growth in plants is not by slow 
and regular modifications, but in rhythms or waves, and that it is the 
varying intensity of these waves that largely influences those variations 
that give character to genera and species. In Corydalis there is a 
sleeping of the buds till the apical bud is reached, which keeps on 
without resting till fully formed. Instead, however, of the next in 
order downward being started into a renewed growth, as in CompositsB, 
it is the lowest on the five-flowered raceme that starts the second growth- 
wave, and the other three upwards then follow successively. 
Heredity of Torsion.f — Herr H. de Vries has established that the 
torsion (Zwaugsdrehung) exhibited by Dipsacus sylvestris is a hereditary 
character, fixed by natural selection. 
(4> Chemical Changes (including Respiration and Fermentation). 
Process of Oxidation in Living Cells. J — Prof. W. Pfeffer presents 
the results of a systematic investigation regarding the action on vegetable 
cells of peroxide of hydrogen. He believes that neither this nor any 
similar substance furnishing active oxygen arises in living cells or exists, 
in the cell-sap. Hence the processes of oxidation in the living cell 
must be effected in some other way than by simple imbibition into the 
protoplasm. 
Formation of Glycogen in Beer-yeast.§ — M. Laurent shows that 
the alcoholic fermentation has well-defined limits, for it is only produced 
when the yeast is supplied with saccharine substances. If the latter be 
replaced by certain other substances (acetates, glycerin, erythrolene), 
an excellent development of Saccharomyces takes place ; but to serve as 
aliment these carbohydrates must be consumed in contact with air. Of 
these substances, the author enumerates thirty-four capable of replacing 
sugar. Not only do these organic substances subserve direct nutrition, 
but some fourteen assist also in forming reserves of glycogen. And an 
old experiment of Pasteur is easily explained from the foregoing facts. 
Beer-yeast diluted with water and left to itself gives off carbonic 
acid and produces alcohol. In this autophagic experiment the yeast 
* Bull. Torrey Bot. Club, xvi. (1889) p. 293. 
f Ber. Deutsch, Bot. GeselL, vii. (1889) pp. 291-8 (1 pi.). 
X Abhandl. K. Sachs. Gesell. Wiss., xv. (1889) 141 pp. See Bot. Ztg., xxxviii, 
(1889) p. 621. 
§ Ann. Inst. Pasteur, 1889, p. 112. Cf, this Journal, 1888, p. 785. 
