ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 
445 
flowers are cross-pollinated, the increase is very striking, and decidedly 
points to the conclusion that insect-visits are the main agency for 
pollination in winter. 
Mr. C. Robertson’s * * * § most recent contribution to the literature of 
this subject comprises an account of the mode of pollination, and the 
insect visitors in species of Adsea, Lespedeza (Leguminosse), Cornus , 
Viburnum, Lonicera (in which one species L. sempervirens is pollinated 
by birds), and Helianihus. 
Experiments on Hybridising.-)- — Mr. W. Saunders gives an account 
of the results achieved by experiments conducted by him during the 
past 25 years, in the “ cross-fertilising ” of plants, trees, and shrubs. 
Among the more interesting hybrids produced were the following : — 
One between the black currant as male and the gooseberry as female. 
A cross was obtained between a form of the wild grape Vitis cor difolia 
and a variety of V. vinifera. A number .of varieties of dark purple 
raspberries were produced between the black-cap raspberry Bubus occi- 
dental is and the red raspberry B. strigosus. Pyrus baccata was also 
fertilised by a Russian apple, and Primus pumila by P. americana. A 
striking hybrid was obtained between Berberis Thunbergii and B. vulgaris 
purpurea . A number of promising new varieties of wheat were also 
obtained. 
Hybridisation of Willows.J — Mr. E. T. Linton has succeeded in 
producing, by artificial pollination, hybrid willows, apparently entirely 
resembling forms which occur in nature. The different species of Salix 
present, however, very different capacities for hybridisation ; some cross 
with great readiness; others with reluctance; others again obstinately 
refuse to enter into any alliance at all. 
Hybrid between Lychnis diurna and L. vespertina.§ — M. F. 
Gagnepain has obtained artificially hybrids between these two nearly 
allied species, — both between L. diurna £ and L. vespertina 9 > and 
between L. vespertina and L. diurna 9 > and gives details of the 
characters in which they combine the structure of the male and of the 
female parent. Subsequently he found both these hybrids growing 
wild, produced by the agency of insect-pollination. 
(2) Nutrition and Growth (including- Germination, and Movements 
of Fluids). 
Action of the Rontgen Rays on the Protoplasm of the Living 
Cell. || — According to Sig. G. Lopriore, the X-rays exercise an ac- 
celerating influence on the current of protoplasm in the cells of Val 
lisneria spiralis ; but this influence does not last long, and, if con- 
tinued for a longer period, the effect is injurious. The action of the 
rays completely suspends the germination of pollen-grains. 
* Bot. Gazette, xxv. (1898) pp. 229-45. 
f Rep. Brit. Ass. Toronto, 1897 (1898) pp. 867-8. 
% Journ. of Bot., xxxvi. (1898) pp. 122-4. 
§ Bull. Soc. Bot. France, xlii. (1896) pp. 129-39; xliv. (1898) pp. 441-9. 
|| Nuova Rassegna, Catania, 1897, See Bot. Centralbl., lxxiii. (1898) p. 451. 
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