Masterpieces of Science 



field, of the British Royal Navy, a man appar- 

 ently of wide information, good judgment, and 

 great energy. 



The same thing occurred when the California 

 people sent this saviour of horticulture to South 

 Africa, where the white scale had also made 

 its appearance. 



It is not only beneficial insects, however, 

 which are being imported, but diseases of in- 

 jurious insects. In South Africa the colonists 

 suffer severely from swarms of migratory grass- 

 hoppers, which fly from the north and destroy 

 their crops. They have discovered out there a 

 fungus disease, which under favorable con- 

 ditions kills off the grasshoppers in enormous 

 numbers. At the Bacteriological Institute in 

 Grahamstown, Natal, they have cultivated this 

 fungus in culture tubes, and have carried it 

 successfully throughout the whole year; and they 

 have used it practically by distributing these 

 culture tubes wherever swarms of grasshoppers 

 settle and lay their eggs. The disease, once 

 started in an army of young grasshoppers, 

 soon reduces them to harmless numbers. The 

 United States Government last year secured 

 culture tubes of this disease, and experiments 

 carried on in Colorado and in Mississippi show 

 that the vitality of the fungus had not been 

 destroyed by its long ocean voyage, and many 

 grasshoppers were killed by its spread. During 

 the past winter other cultures were brought over 

 from Cape Colony, and the fungus is being pro. 

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