31 



Both the melon and the cowpea fungus grew in nutrient gelatin 

 (_|_40, +20, 0, and — 20 of Fuller's scale), but without liquefaction. 

 The melon fungus grew rapidly on glycerin agar. 



In Dunham's solution with 2 pir cent cane sugar and 0.2 per cent 

 sodium carbonate the melon liingti.s made more growth than the cow- 

 l)ea fungus (ascospore strain). After 13 days the former filled the 

 tubes (10 c. c. portions), while the latter had made only a trifling growth 

 on the bottom of the tubes. In each the fungus was browned. 



Both the melon and cowpea fungus made a very insignificant growth 

 on dried ligs steamed in distilled water, the very sweet substratum 

 ajipearing to be unsuitable for growth. 



In acid media, such as the Juice of ripe Concord grapes, the growth 

 of the melon fungus was much retarded, but it finally overcame the 

 inhibiting substances. 



The melon fungus grew well in sterilized horse dung and feebly on 

 rotten wood (soft maple destroyed by wood fungi). 



Bordeaux mixture sprayed upon young melon vines in no way 

 checked the spread of the disease. 



Carbonate of copper mixed with carbonate of lime and put into the 

 hills at planting time, or soon after, did not protect either cotton or 

 melon plants. 



HOST PLANTS. 



Neocosmosjjora occurs on cotton {Gossypiuni herhaceum and G. Barba- 

 dense), watermelon {Citrullus vulyariH), and on cowpea (Fi</nastne«sis). 

 It probably occurs also on okra {Hibiscus esculentus), although the 

 identification is not complete, depending solely on the character of the 

 symptoms, on the presence of similar macro and microcouidia, and on 

 the occurrence of the disease in the same localities, no cultures or 

 cross inoculations of the okra fungus having been made and no peri- 

 thecial fruits having been discovered. 



HABITAT, TIME OF OCCURRENCE. 



This fungus lives from year to year in the soil. It is peculiarly a soil 

 organism, always attacking the plant from the earth. The internal 

 conidia (PI. II, 8, 11; PI. V, 4, 6) occur in the vessels of the living 

 plant throughout the growing season, causing the disease known as 

 "blight" or " wilt''; the external conidia (PI. I, 9; PI. II, 7; PI. V, 3), 

 whenever plants have been killed by the internal funguS'; the perithe- 

 cia, from August to November. 



GEOGRAPHICAL DISTRIBUTION. 



All stages of the fungus have been found by the writer at Monetta, 

 S. C, on watermelons and cowpeas (1894 and 1895), at Charleston, S. C, 

 on cotton and cowpeas (1895), and near Kingstree, S. C, on cotton (1S95). 

 The conidial stages have been found by the writer at Charleston, S. C, 

 in okra and watermelon (1895), and at Chuckatuck, near Norfolk, Va., in 



