446 
SUMMARY OF CURRENT RESEARCHES RELATING TO 
Nitrogenous Nutrition of Plants.* * * § — According to M. L. Lutz, 
flowering plants can derive the nitrogen necessary for their nutrition 
from amines without the previous transformation of these substances 
into ammoniacal salts or nitrates. The elimination of nitrogen takes 
place in the gaseous state. 
Germination of Seeds.f — From a series of experiments, made chiefly 
on peas, M. F. Y. Jodin concludes that the first stages of germination, 
resulting in the production of a rootlet 2-3 times the diameter of the 
seed, can take place without the intervention of an appreciable amount 
of oxygen. Subsequently oxygen is necessary, and this must be sup- 
plied in the uncombined state ; it is not available in the form either 
of nitrate or of hydrogen peroxide. Any reduction of nitrates which 
takes place during germination must be due to the action of microbes. 
Influence of Electricity on Germination.J — Further researches on 
this subject by Sig. G. Tolomei lead him to the conclusion that there is 
no difference in their absorbing power for water of seeds subjected to 
an electric current and of those not so treated. It does, however, some- 
what accelerate the process. 
Germination of the Seeds of Aquatic Plants.§ — According to a 
series of experiments made by Dr. H. B. Guppy, the germination of 
seeds may, in the case of many aquatic plants, be deferred to the third, 
fourth, or fifth year. The seeds of the water-lilies decay rapidly when 
dried, but retain their vitality if kept moist. Immersion in sea-water 
favours, rather than retards, their germination. In the case of the 
majority of aquatic plants, darkness has a decidedly repressive effect 
on their germination ; in other cases it is indifferent ; while seeds of 
Potamogeton natans germinated more freely in the dark. 
Germination of Lathrsea. || — Herr E. Heinricher finds the phenomeua 
of germination in Lathrsea clandcstina to be repeated also in L. squa- 
maria. The first pair of leaves which succeeds the cotyledons possesses 
the hollow cavities characteristic of the rhizome-scales of Lathrsea . 
They are wanting in the cotyledons. 
Effects of Water at Different Temperatures on the Germination of 
the 01ive.1T — According to Sig. N. Passerini, seeds of the olive which 
have been immersed for 10 minutes in water at from 40°-50° C. ger- 
minate more rapidly than those not so treated ; immersion in water at 
60°-70° increases the proportion that germinate ; while a temperature 
of 90° destroys their power of germinating. Under ordinary circum- 
stances it is common for not more than 20 per cent, of olive-seeds to 
germinate. 
Functions of Stomates.** — From a comparative examination of the 
structure of stomates in terrestrial aerial, and aquatic plants, Prof. C. E. 
* Comptes Rendus, cxxvi. (1898) pp. 1227-9. 
t Ann. Agron., xxviii. (1S97) pp. 433-71. See Joura. Chem. Soc., 1898, Abstr. 
p. 129. 
% Atti R. Accad. Lincei, vii. (1898) pp. 177-83. Cf. this Journal, 1897, p. 142. 
§ Proc. R. Pliys. Soc. Edinburgh, 1S97, pp. 344-59. 
1| Ber. Deutsch. Bot. Gesell., xvi. (1898) pp. 2-5 (1 fig.). Cf. this Journal, 1895, 
p. 335. U Bull. Soc. Bot. Ital., 1898, pp. 71-3. 
** Rep. Brit. Ass. Toronto, 1897 (189S) pp. 861-2. 
