90 FUNGOID DISEASES 



Preventive Measures. — 



1. Turn potatoes in the "pie" frequently and 

 remove any rotten tubers. 



2. Rotation of crops (doubtful). 



3. Drain the land well. 



4. Store potatoes in a perfectly dry condition. 

 Pethybridge (" Pro. Roy. Dub. Soc," Vol. XIII, 



No. 35, 191 3, and Vol. XIV, No. 10, 1914) de- 

 scribes a " wet " rot for which he suggests the name 

 pink rot and which is caused, by Phytophthora 

 erytJiJVseptica. Apparently the disease is only of 

 a serious nature on land that has been successively 

 cropped with potatoes ; further observations and 

 inquiries may show that the disease is more wide- 

 spread and the damage greater than is at present 

 thouijht to be the case. 



X. Spotted Tubers. — Like the markings on the 

 leaf, those on the tuber are almost legion in 

 number ; classification is difficult and not very 

 satisfactory. The exact cause of their appearance 

 is in many cases obscure. 



{a) Blotches or Pimples [Spicaria nivea), — Fungi 

 Imperfecti ; Order : Moniliales. 



Much loss has been caused, especially in Scot- 

 land and East Anglia, during the past few years, 

 by a peculiar disease in the form of pimples or 

 blotches. The author first noticed it on the variety 

 "Evergood," which is particularly susceptible, but 

 many or all of the other varieties are attacked. It 



