THE 



SCIENTIFIC PROCEEDINGS 



OF THE 



ROYAL DUBLIN SOCIETY. 



Vol. XII. (K.S.), No. 16. JULY, 1909. 



FUETHER OBSERVATIONS ON 



POWDERY POTATO-SCAB, 8P0NG0SP0BA 



SUBTEBRANEA (Wallr.). 



T. JOHNSON, D.Sc, F.L.S., 



PKOFESSOR OF BOTANY IN THE ROYAL COLLEGE OF SCIENCE FOE IRELAND. 



(PLATES Xll.-XiV.) 



[_A ufhors alone are responsible for all opinions expressed in their Comwunications.'] 



DUBLIN : 



PUBLISHED BY THE ROYAL DUBLIN SOCIETY, 



LEINSTER HOUSE, DUBLIN. 



WILLIAMS AND NOEGATE, 

 14, HENRIETTA STREET, COVENT GARDEN, LONDON, W.C. 



1909. 



Price One Shilling. 



'Ateonian Imtki. 



