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part or all of the leaf. On leafstalks and tendrils as elongated dark 

 lines, which increase in breadth so as to involve the part and 

 cause it to turn black and shrivel. Similar elongated spots, 

 which afterwards become white in the center, mark its stems, 

 but in the case of these woody growths, the damage I have not 

 found sufficient in the specimens examined to be serious, the in- 

 jury being mostly confined to the tenderer parts of the vine. 



The spores of the fungus, which germinated readily, were 

 sown upon a young watermelon plant, grown from seed in the 

 greenhouse; in three days the plant thus affected began to show 

 signs of disease ; in eighteen days the plant was completely dead. 

 An examination of the blackened and wilted leaves showed the 

 pyenidia of the fungus containing the characteristic and well de- 

 veloped sporules. 



The check plant uninfected remained healthy, with no signs of 

 the disease. 



The fungus causing the above trouble is a member of the 

 genus Phyllosticta, although from the character of the sporules, 

 which are sometimes uniseptate and hyaline, it is questionable 

 whether it might not, following Saccardo, be classed as an Asco- 

 chyta. It seems to differ from either P. orbicularis, E. and E., 

 or P. atrbitraccarum, Sacc, found on Cucurbita Pepo, L., and is 

 here described as new. 



Phyllosticta Citntllina, n. sp. 



Spots circulur, irregular, black, concentrically ridged, becoming 

 confluent. Pyenidia amphigenous, brown, immersed, scarcely 

 erumpent, membranaceous, lenticular 75-131 /<, average of many 

 measurements 107 M X 67 /<. Sporules 9- 10.7 /<, average about 

 10 /< X 3.5 jn generally continuous, sometimes uniseptate, straight, 

 slightly curved, ends obtuse, often biguttulate, hyaline. 

 On leaves and other parts of watermelon. 

 Delaware College, Newark, Del., Oct. 27, 1891. 



