1916] 



MEINECKE: PERIDERMIUM AND CRONARTIUM 



227 



FIG. 1. Gall of Peridermium harknessii on Pinus radiata with aecium. Result 

 of direct aecial infection. Note the sharp line of demarcation at the basal end and 

 the incipient witches'-broom formation in connection with the gall. 



