Vol. XV DE^CEIvIBKR 9, 1918 No. lO 



JOURNAL OP 



RESEARCH 



CONTENTS 



Pag« 



Seedling Diseases of Conifers - - - - - - 521 



CARL HARTLEY, T. C. MERRILL, and ARTHUR S. RHOADS 



( Contribution from Bureau of Plant Industry ) 



Histological Studies on Potato LeafroU - - - - 559 

 ERNST Fo ARTSCHWAGER 



( Contribution from Bureau of Plant Indostr;) 



PDBUSHED BY AUTHORITY OF THE SECRETARY OF AGRICULTURE, 



WITH THE COOPERATION OF THE ASSOCIATION OF AMERICAN 



AGRICULTURAL COLLEGES AND EXPERIMENT STATIONS 



V^ASKEINOXON, D. C. 



WASHINQTON : QOVEHNMENT PRINTINQ OFFICE : I8I( 



