Figure 3: Scanning electron micrographs showing surface structures of Streptococcus constellatus strains H39 (H39) and ATCC 27823 (27823), Streptococcus intermedius ATCC 27335 (27335) and Streptococcus anginosus ATCC 33397 (33397). Streptococcus constellatus strains H39 and ATCC 27823 had dense meshwork structures surrounding the cell surfaces, but other strains lacked this phenotype. Thick fibers behind Streptococcus anginosus ATCC 33397 cells are glass fibers of filter paper (33397). Bars=2 μm.