642 



Notes on Insect and Fungus Pests. [nov., 



During the past two months the Board's Inspectors have 

 been engaged in inquiries relating to the prevalence of Wart 

 Disease on potatoes in Great Britain. 

 Notes on Insect, Up to the time of going to press this 



* UngU p' e ™ d ° th6r work had not been concluded, so that 

 no report can as yet be made, but the 

 present opportunity may be taken to refer to some other 

 potato diseases found on specimens sent to the Board for 

 identification. These specimens were mostly sent up by 

 growers who suspected Wart Disease, and in response to the 

 notice issued by the Board warning all persons concerned of 

 the penalties attached to a failure to report, as prescribed 

 by the Destructive Insects and Pests Order. 



Corky Scab (Spongospora scabies, Mass). — This disease, 

 which Prof. Johnson prefers to call Powdery Scab 

 (Spongospora subterranea, Wallroth), is well known to 

 be of old standing in Great Britain and Ireland, 

 and to be widely distributed. It has been reported 

 to the Board from many parts of Great Britain, chiefly, 

 however, from those parts where Wart Disease is also 

 present, or where it has been suspected. Cases have 

 been reported from Peebles, Stornoway, Forfar, Fife, 

 Lanark, Aberdeenshire, Stirlingshire, Lancashire, Cumber- 

 land, Shropshire, Yorks W.R., Staffordshire, Wales, Here- 

 ford, Somerset, and Worcester. In Scotland, therefore, the 

 disease seems fairly widely distributed, but in England, as 

 might be expected, it appears to be confined to the west, 

 where the rainfall is higher. It is not, however, to be 

 supposed for a moment that anything like all affected 

 localities are here recorded. 



The characteristic that seems to have been noticed by 

 most people who reported is the knobs and swellings on the 

 tuber, giving it rather the appearance of having lopped off 

 limbs. These knobs (not shown in the figure) have, no 

 doubt, been mistaken for the symptoms of Wart Disease, 

 and they have generally been reported as such. The speci- 

 mens forwarded have, however, exhibited the disease in 

 every stage of intensity from the first, where only a few 

 spots occur that might easily be overlooked, to a late one in 

 which the tuber was exceedingly distorted. Some of these, 



