The Natural Enemies of Locusts

Fig. T. Redwing Locust, dead from Beauucria globlllifera. (Natural size). that death occurs about six to eight days after infection. The infected insect ceases feeding, wanders aimlessly about, and just before death hides in a shady spot on or near the ground. The bottom of the cane stools are favourite places. After death, the whole of the inside of the insect is full of a white growth of fungus, which shortly pushes its way through the thin membranes between the segments of the abdomen, and appears on the outside as white rings along the body. The dead locust becomes mummified, and the growth of the fungus may continue on the outside till the whole body is covered. On this white growth the spores are produced, which are the source of infection for other locusts. Known originally as Sporotrichum globuliferum, it has a wide range of insect hosts, and an equally wide geographical distribution. It was present among locusts in Natal in 1896 (Cooper), and indeed was artificially grown' and distributed in tubes along with Mucor as the "South African Locust Fungus;" and according to a statement of Howard '. was found in the United States to be the most effective of anv culture which had been tried. The attempt has been made on several occasions to use it as a control against insect pests, but always with results which did not justify its adoption. It was recorded in 1932 on the Philippine Migratory Beauveria Globulifera. Judging by the number of specimens found, this appears to be the disease next in importance to Empusa. It is called the White Fungus Disease, owing to the fact that the dead locust becomes covered with a white cottony growth. It appears By A. McMARTIN, Ph.D., B.Sc.