INSECTS AFFECTING GRAINS, GRASSES, ETC. 109 



The South African Fungus. In 1900 Professor Morgan made a 

 test of a fungous disease which had been found to destroy large 

 numbers of grasshoppers in South Africa, to determine whether, 

 after starting it by artificial propagation, it would spread suffi- 

 ciently to destroy any considerable number of locusts The 

 weather was favorable, rains being frequent. Early in August 

 it was found that " over the areas where the liquid infection 



FIG. 91. Carolina locust killed by fungous disease. (Photo by Weed.) 



was spread diseased hoppers were abundant." "As many as 

 a dozen dead grasshoppers could be found upon a single plant, 

 and some upon nearly every weed on ditch-banks where grass- 

 hoppers were numerous. From the centres of infection great 

 areas had become inoculated, spreading even beyond the planta- 

 tions first infected." The property upon which it was placed 

 became thoroughly infected with the fungus. Strangely, though 

 many other species of grasshoppers were abundant, only the 

 differential locust was killed by it. Dr. Howard states that this 

 disease has also spread and done effective work in Colorado. 

 However, more recent experiments made by the writer in Texas 

 gave only negative results, and it is doubtful if any reliance can 

 be placed upon the artificial use of such fungous diseases for 

 locust control. 



Poisoning. A mash composed of bran, molasses, water, and 

 some form of arsenic, flavored with fruit juice according to formula 

 given on page 57, has been extensively used for grasshoppers 



