Bacillus popilliaeDutky was the major pathogen found in grubs ofCyclocephala parallelaCasey andLigyrus subtropicusBlatchley in Florida sugarcane fields. The milky disease was widespread among fields in the sugarcane-producing region, and two differentB. popilliaevarieties infected the grubs. The type A milky disease, containing a parasporal crystal and spore in the sporangium, was the prevalent variety infectingC. parallela.The type B variety, possessing only a centrally located spore within the sporangium, infected mainlyL. subtropicusgrubs. The overall infection rate ofB. popilliaewas significantly greater inC. parallelathan inL. subtropicus.