DISEASES OF PLANTS. 235 



During 1895 a new stem blight of potatoes was observed upon Long- 

 Island and also in Dutchess and Orange counties. The disease is 

 characterized as follows : 



"First, there is a cessation of growth. The topmost leaves take on a yellowish, 

 or in some varieties a jjurple color, ami roll inward from the edges and upward, 

 exposing the under surfaces. This condition is followed by wilting and comjjlete 

 drying up of the entire foliage, the process taking from 1 to 3 -weeks. The tubers 

 appear to be sound, but when cut at the stem end blackened fibers are seen pene- 

 trating the flesh to a considerable distance, materially injuring it for cooking pur- 

 poses. No rot develops in the tubers. The stem just beneath the surface of the soil 

 first shows discolored spots and later becomes dry and shriveled." 



The disease seems not to be dependent upon weather conditions nor 

 varieties. In some cases it seemed worse ui)on upland soil than on 

 moister lowlands. The author thinks it possible that the disease is due 

 to OUspora rosea, since that fungus is nearly always present in diseased 

 stems after the death of the plants. JSTo thing is known about preventive 

 treatment, spraying not being able to control it. 



The author's attention was called to a peculiar potato trouble to which 

 the name '^ijimply potatoes" was given. Numerous minute elevations 

 are distributed over the surface of the tuber. When examined they 

 were found to be caused by corky deposits under the epidermis and 

 were thought to have originated from insect punctures. From the 

 absence of eggs or larva? the attacks were probably made for feeding 

 purposes. 



A report is given of a new Fusarium that attacks potato stalks. The 

 stalks appear as though girdled iu various places by a pink fungus. 

 The disease appears about midsummer, spreads rapidly for a few days, 

 and then disappears. The fungus was characterized by Ellis and 

 E verhart ' as follows : 



"Fusarium acuminatum. — Sporodichia gregarious, minute, white at first, then flesh- 

 colored, attenuate acuminate at each end, 3 to 5, exceptionally 6 septate, not con- 

 stricted, arising from slightly elongated cells of the proligerous layer, in which 

 respect it differs from the usual type of Fusarium. Quite distinct from F. diplos2}o- 

 rum, which occurs on the same host." 



Bacteriosis of carnations, J. C. Arthur and H. L. Bolley {Indi- 

 ana Sta. Bui. 59, pp. 15-39, pis. 8). — This disease, which appears to be 

 very widely spread, attacks the leaves, being found only rarely upon 

 other parts of the plant, and checks the growth of the plant and 

 reduces the size and number of flowers. It may be recognized by the 

 small pellucid dots scattered irregularly over the leaves, and is said to 

 be of bacterial origin, the organism having been given the name Bacil- 

 lus dianthi. The disease usually starts when the leaves are quite imma- 

 ture and the surface of the leaf may sometimes be slightly raised over 

 the dots, making watery pimples. Later the surface of the leaf above 

 the spot changes, indicating the spot, and as it extends to the inside of 

 the leaf the surface becomes dry, the internal tissues collapse, and 



' Proc. Philadelphia Acad. Sci., 1895, p. 441. 

 6128—1^0. 3 5 



