NOTES AND ABSTRACTS. 



191 



the beginning of the experiment there were days in which the diseased 

 leaves transpired half as much again as the healthy specimens. They 

 ascribe this lower transpiration to hypertrophy, closure of inter- 

 cellular spaces, and absence of stomata. — G. F. S. E. 



Tree Crickets, Notes on. By P. J. Parrott and B. B. Fulton 

 {Jour. Econ. Entom. vi. pp. 177-180 ; April 1913 • figs.). — ^The tree 

 crickets Oecanthus niveus, 0. nigricornis, and 0. quadripundatus , 

 all of which lay their eggs in the bark of trees and other plants, are 

 briefly dealt with, the mode of egg-arrangement and the kinds of 

 plants affected being the main features of the article. The infection 

 of the trees by fungi through the wounds made is also referred to. 



F, 7. C. 



Trees and Shrubs in Ireland. By W. J. Bean {Bull. Roy. Bot. 

 Gard. Kew, 1913, No. 3, pp.^ 106-113). — ^An account of the note- 

 worthy trees and shrubs growing in certain well-known gardens in 

 Ireland. — A. S. 



Trifolium pratense, Pollen of. By J. N. Martin {Bot. Gaz. 

 Aug. 1913, pp. 112-126 ; one fig.). — This paper gives in full a series 

 of careful experiments on the germination of red clover pollen. 



A whole series of sugars of different concentration were tried 

 without any satisfactory result, but when the pollen was placed on 

 moist animal membrane under bell-jars, good germination was obtained 

 in 8-10 minutes. The author concludes that germination is delicately 

 adjusted to the amount of water available. This amount varies 

 within very narrow limits : sugar solution and the secretion of the 

 stigma only affect germination by their influence on the water-supply. 

 Pollen, in self-pollination, germinates readily, but the tubes traverse 

 the style much more slowly than in cross-pollination. — G. F. S. E. 



Vegetable Gardening in Algerian Oases. By Lieut. Nicloux 

 and Mar. des Logis Arzillos {Rev. Hort. de VAlg. Feb. 1913, p. 37 ; 

 March, p. 85 ; and April, p. 125 ; figs.). — ^Three articles containing 

 an account of vegetable growing in an Algerian oasis. The first starts 

 with hints on the choice of the exact site for the garden in cases where 

 choice is still possible, and other points treated of are : hedges and 

 wind screens, extent of the garden in proportion to available labour, 

 the summer garden and the winter garden, analysis of soils, pre- 

 paration of the soil, levelling and the construction of internal 

 walls, garden planning, the choice of suitable tools. A list is given 

 of all the fruits and vegetables which can be grown in such a garden, 

 with a description of the treatment required by each.— ikf . L. H. 



Vegetation above the Snow-line in the Alps. By J. Braun 

 {Ber. d. naturforsch. Schweiz., 1913, 347 pp.).— The author gives an 

 interesting account of the nival (above snow-line) flora of the great 



