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well-known. to growers, but one which has apparently never 
been investigated. In certain districts it has recently been 
on the increase and is responsible for serious losses. It is shown 
to be due primarily to a physiological phenomenon which causes 
the surface tissues to become ruptured, and not to the invasion 
oi a fungus parasite. Cracking takes place during the growing 
season especially if rains follow a dry period, the portion 
involved being the skin, i.e., the periderm and the outermost 
‘layers of the cortex. The cracks, which for the most part run 
horizontally around the upper part of the root but stso in a 
vertical direction, are from 4 to 2 in. long and gape open 
exposing the soft inner tissues. 
The “‘ canker ’’ or decay which follows is shown to be the 
result of the inability of the pear to form a layer of wound 
cork. Though the outer walls of the 
become suberised and few cell-divisions occur no definite 
formation may be favoured by certain methods 
a view to retarding maturation. 
Orner Parsnip DISEASES. 
Erysiphe Polygoni, DC. The Parsnip Mildew. 
This fungus, which attacks many cultivated plants, occurs 
frequently on Parsnips, being found very plentifully in the 
market gardens around Evesham and Wisbech; it has also been 
noted elsewhere. The perithecia are found late in the season 
both on the leaf-blade and the petiole, but especially the latter. 
The attack is not sufficiently severe to necessitate treatment. 
Phyllachora Pastinacae, Rostr. Plantepatologie, p. 511. 
New to Britain. e conidial (Cylindrosporium) stage of 
this species was found attacking a certain number of parsnips 
with great severity in a market garden at Mickleton (Glos.). 
The disease shows itself first as brown spots on the upper 
B 
