New York Agricultural Experiment Station. 183 



vated blackberries in Massachusetts. We have sought for it in 

 Western New York during the past season, but have found only 

 traces of it. 



We have now to report the occurrence of a third blackberry 

 rust which we will call yellow fall rust to distinguish it from the 

 other two blackberry rusts. On May 28 while examining a 

 plantation of blackberries near Oaks Corners, we found several 

 canes bearing rust sori which were bright yellow, 3-10 milli- 

 meters long, conspicuous and located chiefly near the surface of 

 the ground although some occurred well up on the canes. They 

 proved to be uredo sori and contained multitudes of yellow spores 

 which were roundish or often somewhat angular, slightly rough- 

 ened with minute projections, and had a diameter of 23-24//. 

 There were no paraphyses. 



The variety of blackberry affected was Agawam. At this time 

 there was no rust on the leaves except on three or four plants 

 affected with orange rust; but the owner informed us that every 

 fall the leaves were covered with a yellow rust. 



May 29 the same rust was found on canes of wild blackberries 

 at Geneva and on June 13 on wild blackberries at Williamson. 



The next visit to the Oaks Corners plantation was on August 

 15. Over a large portion of it, also in parts of two other planta- 

 tiotas on the same farm, the plants were covered with a con- 

 spicuous bright yellow rust which appeared chiefly on the under 

 side of the leaves. (See Plate XXIV, Fig. 3.) It was most 

 plentiful on leaves of fruiting canes, but also occurred sparingly 

 on leaves of young canes. About a month later the rust was 

 quite as abundant on the leaves of new canes as on the leaves 

 of old ones. At this later date it was also observed on the fruit 

 pedicels and bracts and occasionally on the sepals; and was 

 more frequently found on the upper surface of the leaves than 

 it had been in August. 



The rust on the leaves was the same as that found on the 

 canes in May. Throughout the season we watched for the ap- 

 pearance of teleutospores which would assist in the determi- 

 nation of the species of the rust, but without avail. The only 



