The Fungus Pests of Garden Plants 



of a shapely, solid Turnip, the bulb is divided into a number of 

 coarse, worthless tap-roots, caused either by poverty of the soil, 

 careless cultivation, or a degenerated stock of seed. Those who 

 save their own seed continuously for years are almost certain to 

 become well acquainted with this malady. They will find a change 

 of seed necessary, and at the same time an alteration in the routine 

 of culture. A healthy, vigorous plant, derived from a pure seed- 

 stock, does not easily make Finger-and-toe, but a sound root that 

 stands for food and money. 



The wart-like growths formed upon the roots of Turnip and 

 Cabbage by the little hard beetle known as the Turnip-gall Weevil, 

 Ceutorhynchus sulcicollis, are also quite distinct from Finger-and-toe. 

 By cutting across a malformed root of Turnip or Cabbage it is 

 usually not difficult to determine the cause of the mischief. If it is 

 Finger-and-toe the root will be found filled with decaying matter ; 

 in the case of Weevil attack the small legless maggots will be brought 

 into view ; and if it is merely an instance of reversion the cut root 

 will appear to be healthy. 



Potato Disease. The fungus which attacks Potato crops was 

 formerly known as Peronospora infestans; now it is recognised by 

 scientific authorities as Phytophthora infestans. The mark of its 

 pestilent touch on the foliage, and its destructive effect on the 

 tubers, are unfortunately too familiar in gardens and on farms. 



No. i. 



In dry seasons its energies are restricted, but the scourge is never 

 absent, and during wet summers the parasite does its deadly work 

 on such a vast scale as to create Potato famines. Moisture is a 

 necessity of its existence, and in rotting haulm, decayed tubers, and 



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