Aerobic, non spore forming, gram-positive bacilli that are straight, curved, and club-shaped. They are often seen on Gram stain in a palisade arrangement producing Xs, Y, and AChinese letters@. They produce white, yellow, cream, or gray colored colonies. They can be isolated from humans, warm-blooded animals, plants and foodstuffs. The majority are plant and animal pathogens. A few species are capable of causing disease in humans.