246 THE JOURNAL OF 330TANY 



ation has not j^et been conclusively proved." Mr. Ramsbottom con- 

 troverts this statement, basing his arguments on the following facts : 

 1. The roots of all orchids growing naturally have fungi in their 

 roots, the fungus being always the same species ; 2. The fungi 

 throughout the OrchidacecB are species of Bhizoctonia {s 'ntu 

 Bernard) ; 3. The only fungus bringing about germination is the one 

 from the roots of the parent plant ; 4. Orchid seedlings, both native 

 and cultivated, alvva\'S show the fungus from the earliest stages of 

 development; 5. The fungus must be beneficial, harmful, or of no 

 effect. Comparative experiments show that in the case of Odonto- 

 glossum germination occurs only when the ** Odontoglossum fungus" 

 is present. 



Thp: Tiveniy-seventh Annual Hepot't of the Moss Exchange Chih 

 (Arbroath: T. Buncle & Co., 1922) is pervaded by a sad tone and 

 laments the death of two valued members of more than twenty years' 

 standing — LI. J. Cocks, of Esher, and E. Cleminshaw, of Birming- 

 ham ; also the illness and resignation of the Secretary, Mr. William 

 Ingham, who has so ably served the Club for man}^ years. The 

 Treasurer tells us that the Club has become weakened by death, 

 sickness, and resignation, and that its future management is under 

 consideration. He points out that the Beginners' Section, started 

 under the care of E. C. Horrell in 1900, has tended to split off and 

 become an independent society and is thus a source of weakness instead 

 of strength to British Bryology : amalgamation w^ould reduce the 

 present working expenses. The lists of specimens contributed to the 

 Club show that an increased interest was taken in ^pliagnacecB 

 during the past year. In the critical notes will be found a number 

 of corrections of bryological records for the counties of Worcester, 

 Stafford, Warwick, and Hereford. 



The Journcd of the Department of Agriculture, published at 

 Pretoria, is devoting attention to the noxious weeds of South Africa, 

 which, "owing to the alarming rapidity of their spread in recent 

 years, are becoming increasingly dangerous to pasturage, wool, and 

 other agricultural pursuits." The number for June contains a paper 

 by K. A. Lausdell, Assistant in the Division of Botany, on the ger- 

 mination and growth of Dodder {Cuscuta cliinensis Lam.) with 

 numerous illustrations and suggestions to its eradication. To the 

 same number, the Agrostologist to the Division, Sydney M. Stent, 

 contributes a paper on '* Dubbeltje (2V/6w/i/s terrestris) and Geeldik- 

 kop in Sheep " — the latter being the popular name of a disease mainly 

 caused by the Tribiilus and deriving from it the name trihulosis. 

 "Dubbeltje" is applied also to Eniex australis and Pretrea zangue- 

 barica, which also have spine-armed fruits ; but the Tribulus (of 

 which a figure is given) is the principal culprit. 



PRorESSOB Trelease, of Illinois University, sends us the second 

 edition, revised, of his Plant Materials of Decorative Gardening. 

 By its aid it is claimed that the question "What is that plant? * — 

 "difficult to answer unless flowers are present, because the ordinary 

 Manuals make use of flower and fruit characters — may be answered 

 easily for over 1000 trees and shrubs, including those most commonly 

 planted in the eastern States and in northern Europe, from foliage 



