462 
SUMMARY OF CURRENT RESEARCHES RELATING TO 
either the male or the female parent, most usually the latter. For 
hybrids which thus exhibit no characters of crossing the author proposes 
the term pseudo-hybrids. The phenomenon is not confined to the genus 
Fragaria, but occurs also in Vitis and Bubus. 
(2) Nutrition and Growth (including- Germination, and Movements 
of Fluids). 
Germination of Myristica fragrans.* * * § — Herr A. Tschirch points 
out the purpose of the light lines which are visible to the naked eye on 
sections of the nutmeg, permeating the whole length of the endosperm, 
bordering the rumination-projections, and passing over into open crevices 
near the cotyledons. These lines consist of two or three layers of cells, 
differing in form and in their contents from the rest of the endosperm, 
and furnishing a conducting path for the tips of the cotyledons which 
serve as absorbing organs ; these enter the crevices, and then pass along 
the lines to the other end of the seed, absorbing the reserve-materials 
from the endosperm. 
Influence of Calcium and Magnesium on the Development of the 
Cell. | — As the result of experiments on the growth of species of Spiro- 
gyra , Zygnema , and Mesocarpus, Herr T. Bokorny states that calcium 
has more influence on their development than any other mineral 
ingredient except potassium. In its absence their growth is very feeble. 
The absence of calcium has especially a deleterious effect on the forma- 
tion of chlorophyll ; while the absence of both calcium and magnesium 
acts prejudicially on the development of the nucleus. 
Action of the Water of the Soil on Vegetation.^ — From a series 
of experiments on the growth of plants in different soils — chiefly on 
Eriger on canadensis and Phaseolus vulgaris, and on the production of root- 
tubercles in Lupinus albus — M. E. Gain finds that each species has its 
own optimum of humidity, and that this has a special influence on the 
development of the tubercle-microbe Bhizobium Leguminosarum. This 
optimum further varies in each species according to its stage of growth. 
Saturation of a soil previously dry introduces important perturbations 
in the supply of sap. Transpiration is most energetic when the soil 
is moist. If the optimum of turgescence of a plant is exceeded, trans- 
piration decreases. There is, in fact, at every moment of growth, an 
optimum turgescence for the functions of nutrition. 
Grand Period of Growth in the Fruit of Cucurbita.§ — Mr. A. P. 
Anderson gives a long series of tables and diagrams illustrating the rate 
of growth of the fruit of Cucurbita pepo from the time of fertilisation to 
that of ripening. The development can be divided into three periods: — 
a period of active and continuous increase from the time of pollination to 
the grand maximum ; one of decline in the daily increase, and rise in the 
daily decrease from the grand maximum to the beginning of ripening ; 
* Ber. Pharm. Gesell., 1894, pp. 260-4 (1 pi.). See Bot. Centralbl., lxii. (1895) 
p. 84. f Bot. Centralbl., lxii. (1895) pp. 1-4. 
t Bev. Gen. de Bot. (Bonnier), vii. (i895) pp. 15-26, 71-84, 123-38 (1 pi. and 
2 figs.). 
§ Minnesota Bot. Studies, 1895, pp. 238-79 (10 pis.). Cf. this Journal, 1894, 
p. 369. 
