534 JOURNAL OF THE ROYAL HORTICULTURAL SOCIETY. 



fungus mycelium may persist in the cells of the host for a considerable time 

 without doing any appreciable harm to it, so long as the cultural conditions are 

 suitable for the sugar-beet. — F. J. C. 



Sugar-beet Wire- worm, A Preliminary Report on the. By John E. Graf 

 (U.S.A. Dep. Agr., Bur. Entom., Bull. 123, February 1914 ; 23 plates, 9 figs.). — 

 Little is at present known with certainty of the life-history of this destructive 

 pest, and the bulletin is a preliminary report of investigations carried on since 

 1909. The life-cycle of the sugar-beet wire-worm (Limonius calij 'ornicus Mannh.) 

 probably covers about four years. About one month each is required for the 

 egg and pupal stages ; seven to nine months for the adult stage, during the 

 greater part of which the beetle is in hibernation ; and about three years for the 

 larval stage. — V. G. J. 



Sulphur, Mechanism of the Fertilizing Action of. By E. Boullanger and 

 M. Dujardin (Rev. Hort. d'Alg. No. 11, Nov. 1913, p. 426). — In a preceding note 

 one of these authors has already demonstrated that flour of sulphur applied 

 in very small doses to pot plants exercises a markedly favourable influence on 

 the growth of the plants, this influence, however, being scarcely noticeable if 

 the soil has been previously sterilized. This points to the fact that the sulphur 

 acts only indirectly by arousing the activities of certain useful microbes in the 

 soil. 



This article gives the results of experiments undertaken with the view of 

 elucidating this question. They seem to establish the fact that the favourable 

 effect of the flour of sulphur is due to the stimulating influence which it exerts 

 on the bacteria which convert complex nitrogenous matter into ammonia and 

 also on the nitrifying ferments. The plant finds, in consequence of the presence 

 of sulphur, a larger quantity of directly assimilable ammoniacal salts, but the 

 sulphur merely sets free the ammonia, which is derived exclusively from the 

 nitrogenous elements in the soil, and must be provided by added organic manure. 



M. L. H. 



Tensions in Stem-tissues. By F. C. Gates (Bot. Gaz. lx. p. 235). — The author 

 has made some interesting experiments on the tissues of Amorphophallus. 

 Taking portions of the stem-like petiole, a strip of the cortex, and the entirely 

 stripped pith, he found the former contracted 2*0 per cent, when partly flaccid 

 and 1 o per cent, when turgid; while the pith increased 5*3 per cent, in the 

 first case and upwards of 8 per cent, in the latter. Sachs long ago showed that 

 tensions of a dicotyledonous stem were similar, observing " only an extremely 

 dilute solution capable of causing endosmose can be present, and that this 

 nevertheless [i.e. in cut lengths] causes a very pronounced absorption of water, 

 turgescence, and growth " (Physiology of Plants, p. 573). It would seem that 

 these tensions may play an important part in the ascent of sap by distension 

 and compiession forcing water into the sap-tubes. — G. H. 



Thunbergia Gibsonii (Bot. Mag. tab. 8604). — Tropical East Africa. Family 

 Acanthaceae. Tribe Thunbergieae. Herb, perennial, twining, 4-5 ft. high. 

 Leaves ovate, base cordate-sagittate, 3 in. long. Corolla-tube curved, i£ in. 

 long. Petal lobes 2 in. across, orange. — G. H. 



Tillandsia regina (Bot. Mag. tab. 8596). — Brazil. Family Bromeliaceae: Tribe 

 Tillandsieae. Herb of large size, stemless. Leaves about 30, rosulate, 3^-4^ 

 ft. long. Peduncle, 3^ ft. high, clothed with recurved bracts. Panicle 3^ ft. 

 long ; bracts having rose-coloured margins. Petals 3^ in. long, white or 

 yellow. — G. H. 



Tobacco Insects in Hawaii. By D. T. Fullaway (U.S.A. Dep. Agr., Hawaii 

 Exp. Stn., Bull. 34, May 1914 ; 9 figs.). — The principal tobacco pests are cut-worms, 

 split-worm, pod-borer, horn-worm, flea-beetle, and cigarette-beetle. Many 

 minor pests are encountered, some affecting the plant and some the product. 



The cigarette-beetle (Lasioderma serricorne) attacks the stored product, and 

 the usual method of control is fumigation with carbon bisulphide and hydrocyanic 

 gas. — V. G. J. 



Tobacco Split-worm, The. By A. C. Morgan and S. E. Crumb (U.S.A. 



Dep. Agr., Bur. Entom., Bull. 59 (professional paper), January 1914 ; 3 tables). — 

 This account of the tobacco split-worm (Phthorimoea operculella Zeller), although 

 not complete, contains data not heretofore published. — V. G. J. 



Tobacco Wire-worm in Virginia, The so-called. By G. A. Runner (U.S.A. 



Dep. Agr., Bur. Entom., Bull. 78 ; May 191 4 (professional paper) ; 2 plates, 9 

 tables). — Injury only occurs where susceptible plants are grown on weedy land. 



