Communications. 2T5 



tachments. But in the case of rotting potatoes the nitrogenous 

 cell structure a and t is destroyed by fungoid action and bacteria 

 combined, but the starch is in no case destroyed and may be re- 

 covered by the use of suitable machinery. 



Having received a supply of seemingly healthy potatoes from 

 New Mexico, Ohio and other places, as well as a few diseased tub- 

 ers from Boston and Swanpscott, Massachusetts, I commenced a 

 series of preliminary experiments to test the chemical and struct- 

 ural theories of Dr. Lyon Playfair and the fungoid theories of 

 M. J. Berkeley and other leading mycologists. In each of four 

 glass jars I placed a pint of water. In No. 1 was placed a por- 

 tion of fungus Peronosjyora infestans and the half of an Ohio po- 

 tato remarkable for its healthy appearance. In No. 2 were placed 

 a diseased potato containing Peronospora infestans and the half 

 of a potato received from Santa Fe, New Mexico. In No. 3 was 

 placed the second half of the Ohio potato alluded to, and in No. 

 4 the second half of the Santa Fe specimen. In Nos. 3 and 4 

 was also put one-half ounce of pure sugar, to assist fermenta- 

 tion. These specimens were subject during the experiments to a 

 temperature of about 75° F. The respective jars were examined 

 from day to day. On the sixth day the Ohio specimen in No. 1 

 was found to be rotting rapidly, while the Santa Fe specimen in 

 No. 2 was apparently uninjured. Specimens of Nos. 3 and 4 

 were undergoing slow fermentation. At first the water contain- 

 ing the Santa Fe specimen became more milky in appearance 

 than the Ohio specimen, but the deterioration on the third day 

 was greater in Na 3 than it was in No. 4. On the 20th day the 

 Ohio specimen was entirely dissolved, forming a pulp, while the 

 Santa Fe specimen retained its perfect consistency throughout. 

 On examining the pulp of No. 4 under the microscope, I found 

 that the starch granules were still confined to their cells, no lib- 

 erated cells appearing on the field of view. Bundles of myce- 

 lium and budding spores appeared in profusion between the cells. 

 A few infusorials were present. The odor was slightly sour. 

 The appearance of No. 4, as seen under the microscope, of about 

 eighty diameters, was remarkable as contrasted with No. 3. The 

 latter specimens presented a mass of infusorial life, mycelium and 



