ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 
625 
Fertilization of Papilionaceae.* * * § — Herr E. Loew describes the mode 
of pollination in two species of Papilionaceae that are cross-pollinated by 
the agency of Lepidoptera. 
In Oxytropis pilosa the process is aided by the union of the aim and 
carina into a cone-like body; the visiting insects are chiefly Eucera 
longicornis and Osmia cmrulenta. 
In Apios tuberosa from North America, the structure is different, 
and does not favour the usual process in Papilionaceae, — the pollination 
of the under side of the body of the visiting insect by the pressing of 
both stigma and anthers out of the trough formed by the carina. Self- 
pollination is in this instance prevented by the remote position of the 
anthers and stigma from one another caused by the remarkable coiling 
of the style. 
Lepidopterophilous Flowers-! — Herr A. G. Kellgren enumerates 
thirty-three species of flowers growing on the Omberg, an isolated 
mountainous region in Germany chiefly covered with pine-woods, which 
are pollinated by the agency of lepidoptera. They all belong to the 
order Leguminosae. 
(2) Nutrition and Growth, (including- Movements of Fluids). 
Physiological Function of Phosphoric Acid, f — Dr. O. Loew 
attributes an important function to phosphoric acid in promoting the 
nutriment of the nucleus and the consequent faculty of growth and 
division of the cell. Although cells can live and form starch and proto- 
plasm without the presence of phosphoric acid, their power of growth 
and multiplication is greatly dependent on it. The author regards 
nuclein, of which the cell-nucleus is composed, as a compound of an 
albuminoid with phosphoric acid. Experiments on Spirogyra nitida and 
Weberi showed that the addition of 0 • 1 per cent, of potassium phosphate 
to the nutrient solution in which they were grown, resulted on an 
average in an increase in the cells to nearly double their normal length, 
while their diameter was not materially increased. There was no 
increase in the amount of starch formed, nor in the number of bands of 
chlorophyll. 
Influence of Salt on the Quantity of Starch contained in the 
Vegetative Organs.§ — M. P. Lesage gives the results of numerous 
experiments made on this point with Lepidium sativum. When this 
plant was watered with a liquid containing 12-15 gr. of salt per litre, 
starch disappeared completely, but the author also states that the 
diminution of starch is not proportional to the augmentation of salt. 
Transpiration - current. || — Herr T. Bokorny recommends ferric 
sulphate in a 0*1 per cent, solution as by far the best colouring fluid 
for following the course of the transpiration-current in plants. By its 
use he has determined that collenchymatous tissue is one of the paths 
through which the current passes. By precipitation with potassium 
* Flora, lxxiv. (1891) pp. 84-91, 160-71 (2 pis.). 
f Bot. Sekt. Naturv. Studentsallsk. Upsala, Dec. 5, 1889. See Bot. Centralbl., 
xlvi. (1891) pp. 317 and 343. % Biol. Centralbl., xi. (1891) pp. 269-81. 
§ Comptes Rendus, cxii. (1891) pp. 891-3. 
|| Ber. Deutsch. Bot. Gesell., ix. (1891) pp. 2-9. 
