BULL. 20, DIV. VEQ. PHYS. & PATH., U. S. OEPT. AGRICULTURE. 



PLATE IV. 



Newtnii H.Pierce ad nat dp]. 



GERMINATION OF THE SPORES OF EXOASCUS DEFORMANS. 



A.Hocii &. Cti.Lith.l^alliin.jre. 



