REPORT OF THE SOCIETY 93 



On a macroscopic examination of the diseased canes in the field and labora- 

 tory no superficial fungous growth could be obse;rved. This appeared only 

 when the specimens were placed in moist chambers. An examination of free 

 hand sections of the stems revealed the presence of strands of mycelium in the 

 wood elements. Some of the tracheae were completely plugged with mycelium 

 No evidence of internal fruiting bodies have been found in these examinations. 



Specimens of diseased canes were placed in moist chambers in order to 

 observe any fungous growth which might take place and especially the predo- 

 minate growth on cut surfaces of the canes. 



Small pieces of the internal tissue were used in making initial cultures on 

 nutrient agar. These cultures yielded a very predominant fungous growth 

 closely resembling that isolated by Lawrence in Washington and described in 

 1912 as Acrostalagmus caulophagus, Lawrence. Typical verticillate conidio- 

 phores were produced in abundance, bearing at their tips heads of conidia en- 

 closed in droplets of hygroscopic slime which disappears in solution immedia- 

 tely when placed in water. 



The specimens placed in moist chambers yielded the same fungus on the 

 cut surfaces, fruiting abundantly. On the bark too were found minute scattered 

 tufts 0.25 — 0.5mm. in diameter and height, which on close examination were 

 found to be the conidiophores of this fungus. The heads of conidia varied in 

 diameter from 10-30u with the average from 10-15u. These contained many 

 hyaline spores, oblong to oval in shape and from 3-8ux2-4u in size. 



There is still doubt as to the specific name of this fungus. Carpenter (Jour. 

 Agr. Res. 12, 9: 529-546, 1918) is strongly of the opinion that the fungus des- 

 cribed by Lawrence as A. caulophagus does not differ from Verticillium alho- 

 trum (R. and B.) sufficiently to warrant the adoption of another name. 



In U. S. D. A. Plant Disease Bulletin for Nov. 1, 1922, Dr. C. L. Shear 

 reports the presence of this disease in Michigan, having isolated the fungus 

 from material collected in that state. The presence of blue stem in Ohio and 

 New York State is also reported by R. B. Wilcox and W. H. Rankin respect- 

 ively. In the same Bulletin an infectious blue stem distinct from that described 

 by Lawrence is reported prevalent at Geneva, N. Y. This condition has not 

 been observed in the Niagara district this year, as all material collected has 

 yielded the same fungus in culture. 



