896 JOURNAL OF THE ROYAL HORTICULTURAL SOCIETY. 



second paper the sporangia and aplanospores of Vaucheria piloboloides were 

 studied. It was found that during the four to six weeks' season of its 

 development only spores were formed, and sexual reproduction began only 

 towards the close of the season. The methods recommended by Klebs for 

 producing sporangia were found not to be successful. But sporangia 

 were found by culture in three parts sea-water and one pare of fresh water, 

 or two parts of each, after three days. The author considers that 

 endosmosis is favoured by the change to a weaker salt solution, and 

 that this increases the turgor and so favours sporangium formation. 



G. F. S.-E. 



Sisal Culture. By F. E. Conter (Agric. Exp. Stn. Honolulu, 

 Bull. 4, 1903 ; 5 figs.). — The cultivation of Agave rigicla vars. elongata 

 and sisalana for their fibre (Sisal Hemp) is described, and its further 

 growth in Hawaii advocated. Directions for propagating, planting, har- 

 vesting the leaves, and drying and baling the fibre are given. — F. J. C. 



Sisal Hemp (Agave rigida) (Qu. Agr. Journ. xiv. pt. 4, April 1904, 

 p. 280; 1 plate). — This communication describes the plant which furnishes 

 the Sisal Hemp, with notes as to the soil, preparation of the land, plant- 

 ing, cultivation, harvesting, produce, extraction of the fibre, and cost. 

 These details are given with a view to the introduction of the Agave into 

 Queensland as the source of a new industry. — M. C. C. 



Sisal Hemp Industry (Agave) (Jour. Imp. Dep. Agr. W.I. vol. v. 

 pt. 2, 1904, pp. 150-172). — This is a summary of the information which 

 has been obtained from various sources as to the cultivation and prepara- 

 tion of Sisal Hemp, the produce of Agave rigida var. sisalana. 



After some statistics concerning its cultivation in the Bahamas, this 

 paper goes on to describe the Sisal plant, distribution, soil, cultivation, 

 poling of Sisal plants, extracting the fibre, drying and baling, yield, 

 freight, fluctuation in prices : it proceeds to Sisal cultivation in Yucatan 

 (with two woodcuts). It is stated incidentally that its cultivation on a 

 commercial scale has hitherto been confined to Yucatan, the Bahamas, 

 Turks Islands, Cuba, and Hawaii. Becent plantations have been made in 

 Venezuela, Santo Domingo, and Bombay and Madras Presidencies in 

 India. — M. C. C. 



Sobralia Ruekeri. By R. A. Rolfe (Orrli. Rev. vol. xii. p. 184). — 

 Historical and descriptive particulars are here included. — H. J. G. 



Sobralia violacea alba. By R. A. Rolfe (Orch. Bev. vol. xii. 

 p. 291). — Historical particulars of this white Sobralia, and a description, 

 made from a flower supplied by Messrs. Hugh Low & Co., Bush Hill, 

 Enfield, are given. — II. J. C. 



Soil Management, Investigations in. By F. H. King (U.S.A. 

 Dep. Agr. Year Hook, 1903, p. 159). — The advantages of thorough cultiva- 

 tion are here fully set out, and where the rainfall is intermittent it is 

 shown to be most important for intertilled crops, like Corn and Potatos, 

 that fields receive good cultivation to a depth of three inches. This is 

 needed (1) to lessen the bad effects of drought by reducing surface 



