[Electron microscopic study of the Rybinsk water reservoir microflora]

Microflora of the Rybinsk water reservoir was studied by electron microscopy throughout the year. Common and rare bacterial forms were revealed which had not been detected before by light microscopy. The following forms prevailed: rod-like, coccoid, and bacteria of the vibrion type. Rare species were confined to certain places of the reservoir and related to seasonal changes in it. Bacteria belonging to the Planktomyces genus were registered in the central part of the reservoir in July--August. Swamp waters always contained bacteria belonging to the Hyphomicrobium genus. Spirillar bacterial forms were constantly present in coastal waters.