Any of a group of diseases beetle of scarabaeid larvae, caused by species of the genus Bacillus; type A milky disease of the white grub of the Japanese beetle (Polillia japonica) is caused by Bacillus popilliae, whereas type B milky disease (marked by extensive formation of blood clots, impairment of circulation, and gangrene of the appendages) is caused by Bacillus lentimorbus....