100 JOUENAL OF THE EOYAL HORTICULTURAL SOCIETY. 



NOTES AND ABSTRACTS. 



Aloe dichotoma. By Leonhard Lindinger (Beih. Bot. Centralbl. 

 xxiv., Erste Abth., Heft 2, pp. 211-253 ; with 4 plates). — A particularly 

 fine specimen of this species having succumbed to disease in the Hamburg 

 botanical garden, the author was enabled to make a thorough microscopic 

 examination of its anatomical structure. 



The branching is not truly dichotomous, for remains of a terminal 

 flower axis can be found in the forks. The number of branches is not 

 more than two or at most three. Axillary buds are not produced 

 regularly. 



The plant shows distinct adaptation to resist extraordinarily dry con- 

 ditions of atmosphere, but in the author's opinion (contrary to that expressed 

 by Schenck) it obtains water from the soil by means of its roots. As the 

 upper layers of the soil are often dried up and strongly heated by the 

 sun's rays, the upper part of the root is provided with a well-marked cork 

 layer. 



Many, if not all, giant succulents and xerophytes are subsoil water- 

 plants. They have the power of growing vigorously when conditions are 

 favourable, and require for this as much water as, if not more than, other 

 plants. Aloe arbor escens puts out new growing roots when the earth 

 becomes dry, and these grow rapidly when the plant is watered. 



As regards the growth in thickness of the stem, the author considers 

 that it is not a continuous process, but is active during favourable conditions 

 only, so that it can be compared to the ordinary increase in thickness of 

 dicotylodons. Aloe succotrina produces every year one ring of vascular 

 bundles and a clearly limited zone is also formed every year in Yucca 

 filamentosa, which last is not injured by the German winter. 



The author considers that the monocotyledons are descended from 

 tree-like forms with secondary growth in thickness. This ancient character 

 is retained in the arborescent Liliiflorse. The aerial stems of other 

 monocotyledons may be different, and the result of a phytogenetically 

 younger method of growth. — G. F. S.-E. 



Alpine Garden at Bourgr St. Pierre. Anon. (Gard. Clwon.^ 

 No. 1134, p. 216, fig. 93, September 19, 1908). — An interesting account is 

 given of the Jardin Botanique de la Linnea at St. Pierre, a small village 

 on the St. Bernard Pass between the Hospice and Martigny. The garden 

 is situated about 5,550 feet above the sea level. It is managed by an 

 international committee, the director being the well-known botanist 

 M. Correvon. A very large collection of Alpine plants will be found in 

 cultivation — not only those which are natives of Switzerland, but others 

 from all parts of Europe, Siberia, and the Arctic regions. — G. S. S. 



Alpinia braeteata (Bot. Mag., tab. 8237). — Nat. ord. Scitamineae ; 

 tribe Zingiberaceae ; Eastern Himalaya. Perennial herb with a stem 



