Medusa head colonies on nutrient agar are seen in
On agar plates, irregularly round colonies are formed by anthrax bacilli, 2-3 mm in diameter, raised, dull, opaque, greyish with a frosted glass appearance. Under a microscope, the edge of the colony is composed of long, interlacing chains of bacilli, resembling locks of matted hair. This is called a Medusa head appearance. Reference: Textbook of Microbiology; Anathanarayan and panicker's; 10th edition; Page no: 251
Pneumococcus
Legionella
Brucella
Anthrax
Bacteriology