Murrill: Field Meeting of Pathologists 311 



insect work. All of these injuries may possibly have been due to 

 the " mosaic," or " calico," disease, which renders the leaf thin 

 and sickly, and unable to resist sudden changes in atmospheric 

 conditions. Many plants showed yellow lower leaves, doubtless 

 due to lack of potash or other fertilizer trouble. 



Tobacco mosaic, like potato mosaic and peach yellows, is a very 

 widespread and mysterious disease. It may be carried far and 

 wide through the field by simply touching the leaves with infected 

 hands. In old plants, if the lower leaves are touched, they will 

 not take the disease, but will communicate it to the younger leaves 

 and suckers at the top. The danger to the crop comes in handling 

 the seedlings, which if infected develop into weaker plants of less 

 value. When the crop is far advanced, there is little need for 

 caution, since the sources of infection are always destroyed dur- 

 ing the winter. 



On Thursday afternoon, after an excellent lunch at Thompson- 

 ville, the Havana tobacco district at Suffield was visited and an 

 inspection made of various experiments in progress there under 

 the direction of Mr. Clayton. Johnson's susceptible burly, grown 

 for comparison, was found to be badly affected with Thielavia 

 root-rot, which turns the tips of the roots brown or black, while 

 in Ftisariiim root-rot the lesions are lighter in color. These rots 

 are readily seen after the roots have been rinsed in water. 



The last stop of the day was made at the extensive tented fields 

 of the American Sumatra Tobacco Company, where 290 acres 

 are under cloth costing a million dollars, and 67 acres are covered 

 by a single tent. The yield this year is enormous, probably be- 

 cause of the plentiful rains. After several bad years, a number 

 of growers in the district had turned their fields out to rest or 

 were cultivating them in corn, timothy, and other crops for a 

 change, which seemed unfortunate in view of the present tobacco 

 yield. 



This company is transporting men, women, and children by the 

 hundreds in motor trucks from Hartford to harvest the crop. 

 The lower leaves are taken off, four or six at a time, as they ripen 

 and hauled in covered baskets to the barns, where they are strung 

 on cords fastened to sticks and hoisted into the barns to dry. In 



