Direct Ultra‐violet and Ultra‐violet Negative Phase‐contrast Micrography of Bacteria From the Stomachs of the Sheep

SYNOPSIS Bacteria from the stomachs of sheep have been examined by direct ultra‐violet and ultra‐violet negative phase‐contrast micrographs. These micrographs show details in the rumen organisms which were poorly or not received by visual light methods. In the abomasum, the acid‐stomach of the sheep, signs of disorganization and disintegration of the bacteria were evident. Material which absorbed strongly in 2749 Å. wavelength was often seen to be concentrated at the edge of the. cells and sometimes in internal granules in the cells in the abomasum. Loss in rigidity and rupture of the cell walls were also often seen in these cells. Some of these degenerative changes appeared to start in the omasum of the sheep. In the rumen the presence of strongly absorbing material outside the cell membranes in some bacteria was marked. In some cases it took the form of a fringe; in others it crept between the septa dividing two units as an apparently homogeneous layer.