Using a fluorescence microscope and EPMA,abundant microbe "bodies" and clear microbic fluorescent microstructure are determined in the ferromanganese nodules recently collected from the East Pacific deep sea floor.The microbic fluorescent structure shows a close relation to the formation of the ferromanganese nodules.According to their morphological features,the microbes are classified into two types:one is named clumpy microbe,which takes a bar-shaped manganese mineral as a pillar and grows like fasciculate coral,resulting in irregular cauliflorate nodules with rough surfaces; the other is called filamentous microbe,which grows in very thin arcuate and/or concentric circular laminae composed of a microbe layer and a metal (manganese and iron)-rich layer,leading to potato-shaped nodules with relatively smooth surfaces.It also can be seen that the two types of microbes are intergrown together,resulting in nodules complicated in compositions and shapes.