False-colour transmission electron micrograph (TEM) of Bacillus subtilis, showing an individual, rod- shaped, Gram-positive bacterium beginning to divide by binary fission. The densely coloured cell wall (pink) appears pinched at the point of division. B. subtilis also propagates itself by producing endospores (resting cells) which germinate & give rise to vegetative cells. The species is occasionally pathogenic in man, causing severe eye infections (iridocyclitis or panopthalmitis). Magnification: X 10, 000 at 35mm size, x20,000 at 6x7cm size.