Three organisms inoculated onto blood agar, straight line inoculation, to demonstrate hemolysis. From top to bottom:
Streptococcus pyogenes: beta, complete lysis of red blood cells, clear area around colony growth.
Streptococcus bovis: alpha, incomplete lysis of red blood cells, green area around colony growth.
Enterococcus faecalis: gamma, growth with no blood cell lysis.
Image taken using transmitted light.