51 
‘Commercial formalin (= 40 per cent. aSTaRIE Paes has proved 
to be the most effective fungicide for sterilising infect In 
the United States, where Thielavia proves ver Sealicetsay in 
causing a root-rot of tobacco seedlings, the soil of the seed-beds is 
thoroughly soaked with a solution of formalin in water, in the pro- 
portion of one pint of formalin to twelve gallons of water. ne 
gallon of the mixture should be allowed for each square foot of 
surface. After the watering is completed the soil should be covered 
for two or three days with coarse sacking or canvas, to keep in the 
fumes. The watering should be done after all digging has been done 
and when the seed beds are in a condition ready for sowing, an 
week or ten days should intervene between the soaking of the soil 
and the sowing of seed, to allow = = complete escape of the 
formalin fumes and the ‘dryin g of the 
When green manure is dug into fad intended for seed beds it 
a previously be thoroughly watepen with formalin as above. 
essor Benincasa has quite recently conducted a series of ex- 
velista: as to the best means of checking root-rot of tobacco in 
seed-beds. Having proved that infected soil is the usual source of 
injury, and that heating such soil to a temperature of 90° oes 
not completely eradicate the disease, comparative tests were made 
by using ordinary garden soil, pure sand, and volcanic ash or pumice 
for seed-beds. The plants ace in garden soil were badly in- 
fected, seed-beds of sand proved v efficient in controlling the 
disease, volcanic ash gave the best pi of all, both in arresting 
the disease, and in the rapid and vigorous growth of the seedlings. 
This result is partly due to the absence of humus, which favours 
the continuous growth of the fungus in soil ere organic 
matter, and also to the physical conditions of such s 
The author suggests the use of coal ashes, Hieaaie scoria, 0 
naturally or artificially powdered volcanic rocks, as suitable for the 
formation of seed-beds. 
LITERATURE. 
Aderhold, R. Arb. Biol. Abt. Land. Fortw. Kaiserl. Gesund. 4, 
p. 463 (1905). 
Benincasa, M. Bul. Tec. Coltiv. eg oe p. 3 (1911). 
Berkeley, M. J. and Broome, C. E. Amn. Mag. Nat. Hist. 5, 
p. 461 (1850). 
Capelluti, Altomare, G. KR. Inst. Scafati, p. 137 (1902). 
Clinton, G. P. Comm. Agr. Expr. Sta. 1907, p. 342 and 1908, 
3 
Massee, G. Journ. Roy. Micr. Soe. 4, p. 841 (1884). 
Orton. W. A Yearbook U.S. Dept. haw 1901 and 1903. 
Peglion, V. Atti Reale Acad. Lincei, 6, p. 52 (1897). 
Saccardo, P. A. Syll. Fung. 1, p. 39 (1882) ; 4, p. 257 and 386 
Scie i. Hedw. 15, p. 113 (1876). 
Thaxter, R. Ann. Rep. Conn, Exp. Sta. p. 166 (1892). 
Zopf, W. Sitz. Bot. Ver. Prov. Sraadesk 18, p. 101 (1876). 
Zopf, W. Die Pilze, p. 91 (1890). 
Zopf, W. Zeitschr. Pflanzenkr, 1, p. 72 (1891). 
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