Case 68. 

Methylene blue stain for cultured Klebsiella pneumoniae
　 　 　 　
　
Capsule formation is evident in the cultured microbes (oil immersion).
 　
　 　 　 　

　

 　 Representative capsule forming bacteria include K. pneumoniae, N. meningitidis, H. influenzae, and P. aeruginosa.