832 



JOURNAL OF THE ROYAL HORTICULTURAL SOCIETY. 



Luxembourgiaeeae, The. By Ph. v. Tieghem (Ann. Sc. Nat. Bot. 

 xix. pp. 1-96 ; 1904). — The author describes features of systematic 

 interest for the genera of this order, and discusses their grouping, as well 

 as the affinities of several doubtful genera. — W. 67. S. 



Lysichitum camtschatcense. By W. H. (Gard. Ghron. No. 908, 

 p. 322, figs. 140 and 141, May 21, 1904).— This remarkable Aroid is the 

 only member of the genus, and has an extensive distribution, being found 

 over a wide area in North-Eastern Asia and North-Western America. It 

 has been grown for some years at Kew, but it flowered for the first time 

 early in April 1903. It is a very effective plant ; the spathe is of a bright 

 yellow colour, and is from 4 to 6 inches in length. The spadix is from 



3 to 6 inches long, and the flower grows on a footstalk about a foot in 

 length. The flowers, when mature, emit a most fetid odour. — 67. S. S. 



Lysichitum camtschatcense. By W. B. H. (Bot. Mag. t. 7937).— 

 Native of North- Eastern Asia and North- West America. Nat. ord. 

 Aroidca ; tribe Orontiece. This is a stout marsh herb, with a spadix 



4 to 6 inches long, within a boat- shaped pale yellow spathe. The leaves 

 are erect, 1-2 1 feet long. — 67. H. 



Lysimachia Henryi. By W. B. H. (Bot. Mag. t. 7961).— Native of 

 Western China. Nat. ord. Primulacece ; tribe Lysimachiece. A vigorous 

 trailing perennial herb. Leaves lanceolate ; flowers yellow, 1| inch 

 diam. — 67. H. 



Madeira, R. Brown's List of Plants. By J. Britten (Joum. Bot. 

 493, pp. 1-8 ; 494, pp. 39-46 ; 498, pp. 175-182 ; and 499, pp. 197-200 ; 

 1/1904, 2/1904, 6/1904, and 7/1904).— A transcript, rearranged and with 

 modern names added, of a manuscript list by Eobert Brown, now in the 

 Botanical Department of the British Museum, enumerating about 600 

 species from the collections of Banks, Solander, and Masson (1768- 1785), 

 most of which is given in Leopold von Buch's " Beschreibung der 

 Canarischen Inseln " (1825), pp. 189-199. This is the earliest published 

 attempt at a Madeiran Flora. — 67. S. B. 



Mammillaria elongata, Observations on. By O. V. Darbishire 

 (Ann. Bot. xviii. July 1904, pp. 375-412 ; 2 plates). — The author's main 

 results are as follows : — The set of spines by which the tubercles of 

 Mammillaria are crowned form a structure which acts as a screen, pro- 

 tecting the underlying tissues of the tubercle from strong sunlight. Such 

 organs are named jjaraheliodcs. In Mesembryanthemum stellatum the 

 set of hairs found at the top of the leaf also form a paraheliode. 



The tubercle of Mammillaria represents morphologically the leaf-basis 

 and possibly, in addition, a portion of the stem. The spines are modified 

 portions of the leaf- blade. One axillary bud is found in connection with 

 each tubercle or leaf. The guiding principle which underlies the adapta- 

 tion of plants and the production of plant forms is physiological. 



Mammillaria elongata was alone investigated, but the physiological 

 results obtained may be made to include other members of the order. 



A. D. C. 



