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JOURNAL OF THE ROYAL HORTICULTURAL SOCIETY. 



very freely, and respiration is much more rapid if much moisture is 

 present, while the length of life is inversely proportional to the extent of 

 respiration. Respiration is, however, not essential to the retention of 

 vitality by the seed, and even though respiration be entirely prevented 

 seeds will continue to deteriorate and sooner or later will lose their 

 vitality. — F. J. C. 



Seeds, Vitality of Buried. By J. W. T. Duvel {U.S.A. Dep. Agr. 

 Bur. PL hid. Bull. 83 ; 8 1905 ; 3 plates). — Seeds of many plants were 

 buried at various depths in porous pots filled with clay soil, and their 

 vitality is to be tested at intervals. 109 species, representing eighty- 

 four genera belonging to thirty-four different families, are being tested. 

 The present bulletin gives the result after the first year. Thirteen 

 species, including shepherd's purse, hemp, and evening primrose, 

 completely failed ; but the author is of opinion that the results here are not 

 quite reliable. Twenty-four either decayed or germinated and afterwards 

 decayed while buried, including maize, corn cockle, cabbage, wheat, 

 beans, barley, onion, and melon. 



Of the remainder the number germinating varied from 5 per cent, in 

 Festuca elatior to 96-5 per cent, in chickweed. 



" In general the pernicious character of weeds is directly proportional 

 to the length of time the seeds will retain their vitality when buried in 

 the soil." 



" The deeper seeds are buried, the better is vitality preserved." 



F. J. C. 



Shelter to Cultivated Plants. By E. J. Russell, D.Sc. (Garri. 

 Chroh. No. 953, p. 193, Apl. 1, 1905). — In mentioning the advantages 

 and otherwise of giving shelter to plants, the author says : " Before our 

 knowledge can advance beyond the empirical stage, it is necessary to 

 examine in some detail the effects produced by shelter. I shall consider 

 the question in its two aspects, as it affects the soil and as it affects the 

 plant, and it will be the most convenient for my preserlt purpose to begin 

 with the soil." He then proceeds to discuss the matter under these two 

 heads in a very interesting manner. — G. S. S. 



Silene glaueina. By F. N. Williams (Joum. Bot. 514, p. 282 ; 

 10/1905). — Description of a new species resembling the Algerian 

 S. Aristidis, collected by G. F. Scott Elliot in crevices of rocks at an 

 altitude of 840 metres (2,750 feet) on Yirgen Hill, in the Andes of Chile. 

 The flowers are white, in 8 to 10-flowered capitulate racemes. — G. S. B. 



Silver-leaf Disease. Anon. (Gard. Chron. No. 971, p. Ill, Aug. 5, 



1905).— Prof. Percival has recently been making some experiments 

 tending to show that this disease is caused by a fungus belonging to the 

 genus StcreiLm. Plum trees, after being inoculated with this fungus, 

 soon begin to show that they are infected by this disease by their leaves 

 assuming the well-known colour. " The mysterious part of the business 

 is that no fungus threads are to be found in the leaves, and so it is 

 conjectured that the disturbance is caused by some ferment or enzyme 



