NOTES AND ABSTRACTS. 



229 



NOTES AND ABSTRACTS. 



Acclimatisation Experiments in Minnesota : Report of the 

 Montevideo Trial Station. By L. R. Mover (U.S.A. Hort. Soc. 

 Minnesota Hep. 1902, p. 51 ; 4 figs.). — The following trees and shrubs are 

 under trial and are reported useful for growth in the prairie district : 

 Lycium halimifolium (but spreads too rapidly) ; Lepargyrea argentea^ 

 more commonly known as Shepherdia argentea, the Buffalo Berry, fruits 

 well ; Elceagnus argentea ; Morus alba tatarica, fairly well established, 

 fruit attracts birds from the Cherries ; Spiraea Van Houttei, the best 

 of the spring-flowering shrubs ; S. sorbifolia ; S. salicifolia, has larger 

 flowers than in wild state ; Neillia opnlifolia syn. Opulaster opulifolius, 

 the golden-leaved form being not quite so hardy as the type ; many 

 species of Philadelphia, P. coronarius seems the least hardy ; the bush 

 Honeysuckles are all very hardy, Lonicera tatarica, L. tatarica speciosa 

 (L. splendens), L. tatarica parvifolia (L. gracilis), L. Buprechtiana, 

 L. Murroivi, L. Suttivantii, are mentioned ; Acer Ginnale ; Pinus 

 montana appears to be the hardiest of Pines ; Picea pungens, the foliage 

 being somewhat browned during severe winters ; P. canadensis, perfectly 

 hardy, 11 there are no safer trees of any kind." — F. J. C. 



Acidanthera Candida.— By Sir J. D. Hooker (Bot. Mag. tab. 

 7879). — Nat. ord. Iridece, tribe Ixiece. Native of East Tropical Africa. 

 Two, of about 18 species in the genus, have been figured ; viz. tabs. 7393, 

 618, and 1531. This is a slender glabrous herb, with leaves 1 to 1\ ft. 

 long. Flowers white, very sweet-scented, 2 in. across. — G. H. 



Acidity Of Plants. By A. Astruc (Ann. Sc. Nat. (Bot.) xvii. pp. 1- 

 108 ; 1903;. — The acids contained in the sap of plants have had various 

 functions ascribed to them : e.g. they neutralise bases which might be 

 injurious ; they take part in the formation of albuminoids ; they are 

 necessary for turgescence of cells and organs, and play an important part 

 in water storage in succulent plants ; they assist transpiration, root-action, 

 oxidation in the plant, &c. This paper gives the results of investigations 

 on the occurrence of free or partially combined acids in different plants, 

 and in various parts of the same plant under varying conditions. Part I. 

 deals with non- succulent plants, and the chief conclusions are : — (1) Leaf. 

 Vegetable acids are present in greatest quantity in young leaves, and 

 diminish as the leaves become older, and the younger parts of a leaf 

 contain more acid than maturer parts of the same leaf ; the organic acids 

 are gradually fixed by saturation or etherification, and disappear as free 

 acid ; the production of organic acids is intimately associated with the 

 processes of respiration and assimilation ; the green parts of variegated 

 leaves are richer in acids than pale parts ; in etiolated plants the acids 

 increase on exposure to light. (2) Stem. The greatest acidity is in young 

 growing parts. (3) Flowers. Acidity decreases as development goes on, 



