ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 555 



Ornithophilous Plants.* — R. Marloth states that there can be no 

 •doubt that in South Africa tho honey-birds (locally known as sugar- 

 birds and sun-birds) visit flowers primarily for the sake of the honey, 

 though they do occasionally feed on insects. He names a number of 

 additional species of Erica which are fertilised by honey-birds. Alto- 

 gether 4.0 species of South African plants, belonging to 19 genera and 

 12 families, are at present known as being regularly visited by Necta- 

 rinieee, including 12 species of Cynniris and 2 of Promer&ps. In the 

 Proteaceaa, of which 13 ornithophilous species are known, cross-pollina- 

 tion is rendered almost inevitable by the very strongly pronounced 

 proteraudry. The very strong hairiness of the ovary of Protect mellifera 

 does not assist in pollination, but in the dispersion of the seeds. 



Hybridisation of Peas and Beans.f — F. Tschermak gives the details 

 of a large series of observations made with the view of determining 

 iihe relative value of different characters in influencing the results. 

 Among other points he notes that no direct influence could be detected 

 of the pollen on the seeds, especially on the form of the cotyledons, or 

 on the colour of the testa. He maintains the possibility of the strength- 

 ening of ancestral characters in the hybrid ; also the production, in 

 particular cases, of new characters not possessed by the parent forms. 

 Two undoubted cases are recorded of the appearance in this way of 

 entirely new characters. 



Physiology of Reproduction.^ — Dr. G. Klebs sums up his general 

 conclusions, already published, with regard to the antagonism between 

 growth and reproduction, by which term he understands the formation 

 of germs which detach themselves from the parent plant, and which are 

 distinguished in form and structure from the vegetative parts of the 

 plant. A brief resume is given of all important researches on repro- 

 duction published during the last few years. 



(2) Nutrition and Growth (including Germination, 

 and Movements of Fluids). 



Capacity of Plants to live without Oxygen. § — From experiments, 

 made chiefly on Zea Mays, A. Nabokich concludes that tho growth of 

 the higher plants does not, in most cases, cease when altogether deprived 

 of oxygen ; nor do they become entirely insensitive to external irritations. 

 No formation of chlorophyll appears to take place, even when exposed 

 to light. It is probable that some seeds can germinate without oxygen ; 

 but this does not appear to be the case with the spores of fungi. 



Carbon-dioxide Assimilation of Leaves in Winter. || — F. Czapek 

 confirms the statement of previous observers that, in our climate, leaves 

 which persist through the winter lose their starch in the late autumn, 

 starch-grains being again formed in the chloroplasts in early spring. 

 The stomates are closed throughout the whole winter, and the starch has 



* Ber. Deutsch. Bot. Ges., xix. (1901) pp. 176-9. Cf. this Journal, ante, p. 435. 

 f Tom. cit., pp. 35-51. 

 • X Op. cit., xviii. (1900) Gen.-Vers.-Heft, pp. 201-15. Cf. this Journal, 1900, p. 701. 

 § Op. cit., xix. (1901) pp. 222-36 (5 figs.). 

 J| Tom. cit., pp. 120-7. 



