630 
SUMMARY OF CURRENT RESEARCHES RELATING TO 
Germination of Jerusalem Artichoke.* — Mr. J. R. Green states 
that during the germination of the Jerusalem artichoke the tubers 
develope a ferment which is capable of transforming inulin into sugar. It 
can be extracted from the tubers by glycerol, and can be artificially 
formed in them by heating for twenty-four hours at 35° C. The sugar 
formed does not crystallize, and reduces less readily than dextrose or 
levulose. 
(2) Nutrition and Growth (including 1 Movements of Fluids). 
Transport of Reserve-materials from the Endosperm to the Em- 
bryo.f — Herr W. Hirsch describes the contrivances for the transmission 
of the reserve food-material from the endosperm (or peri sperm) of 
albuminous seeds to the embryo on germination. These may be arranged 
under four heads: — (1) In large seeds where the embryo is small and 
more or less nearly central, the reserve-cells of the endosperm are more 
or less elongated, and radiate towards the embryo. (2) In very small 
seeds in which the endosperm consists of only a very few layers of cells, 
no such elongation occurs, but the walls of the cells are often very 
strongly pitted. (3) The cell-walls of the endosperm-tissue are very 
thin, and its cells are brought into contact with all parts of the embryo 
by the spirally-coiled form of the latter. (4) The elongation and 
radial arrangement of the endosperm-cells is accompanied by the 
presence of a well-developed absorbing organ. 
In all albuminous seeds which have not a special absorbing-organ, 
its functions are performed by the layers of the endosperm which 
are in immediate contact with the embryo possessing the property of 
swelling up strongly, their contents being then transferred to the epiderm 
of the embryo. 
Relation between Temperature and Growth. :J— Herr E. Askenasy 
describes in great detail the results of a series of experiments to deter- 
mine the relationship between growth and temperature in the case of 
roots of young plants of maize. The optimum temperature was found 
to be between 26° and 29° C., the slowest growth at this temperature 
being 1 • 7, and the most rapid 3 * 8 mm. in an hour. He asserts that 
in all circumstances the growth of the protoplasm is the primary 
phenomenon, the growth of the cell-wall being entirely dependent on it. 
The turgidity remains the same at different temperatures, and therefore 
cannot be the cause of the variation of the rate of growth with the 
temperature. The author does not think that recent observations prove 
the impossibility of the growth of the cell-wall by intussusception. 
Growth of the Leaf-stalk in Water-plants.§ — Prof. G. Arcangeli has 
attempted to investigate the laws by which the stalks of floating leaves 
adapt themselves as to length to the depth of the water in which they 
grow, the growth ceasing when the lamina reaches the surface. In the 
case of Euryale ferox he believes that this is mainly due to the traction 
on the tissues of the leaf-stalk resulting from the lamina of the leaf 
* Ann. Agron., xv. p. 569. See Journ. Chem. Soc., 1890, Abstr., p. 656. 
t Ber. Deutsch. Bot. Gesell., viii. (1890) pp. 1-8. J T. c., pp. 61-94. 
§ Nuov. Giorn. Bot. Ital., xxii. (1890) pp. 121-9, 300-3 (1 fig.). 
