False-colour transmission electron micrograph (TEM) of Haemophilus influenzae (Pfeiffer's bacillus), a Gram negative, non-motile, non- sporing species of bacilli (rod-shaped bacteria). H. influenzae is exclusively a parasite of man, living in the upper respiratory tract of healthy individuals. Most sub-species are non-capsulate bacteria, but there are 6 types of capsulated strains (types a to f), of which type b is responsible for numerous incidences of bacterial meningitis in young infants. Other type b diseases include epiglottitis, a potential cause of fatal obstruction in airflow to lungs. Magnification: x15,000 at 35mm size, x30,000 at 6x7cm size.