130 
he: important result is.that free acid present in the soil is favourable 
organism, while a free alkali i ~ unfavourable.. . This explains the 
KA belief that sulphurie acid favoured the disease, though the sugges- 
tion that this was due to the iphis present is, it would seem now, not 
to be the true solution. 
The following account is extracted from Mr. Massee’s paper printed 
ci 
Several common weeds are also attacked, namely, charlock (Brassica 
Sinapistrum,.Boiss.), garlie-mustard . (Sisymbrium Alliaria, Scop.), 
treacle-mustard (Erysimum.,Cheiranthoides, Linn.), and shepherd’s 
purse (Capsella Bursa-pastoris, .)..,The last-named is reported 
from the United States by Halsted, */and has not been observed to be 
seased in Bri 
mining the true cause, distinctly states that i Uy d examination 
revealed. the, presence ‘of a. factor previously unknown: in. connexion 
with plant din Furthermore, Berkeley oray x that wood 
ashes ware a gnag fon dine digno 84: 2 supposed. £ this. to. be due to the 
-of potash salts in the ash. ; 
Plasmodiophora Brassiee, Wor. (after von Tubeuf). 
-The fo lowing... oi an account of, experiments conducted during four 
successive years 
E Ném-déipep Agrio. Coll. Expt. Station; Bull., 98 (1899). apo 
4 Gard, Chron; p. 500, 1856. : | 
