Five new species of Pythium are described, following ecological studies of the genus in the Reading (U.K.) area. Two of the new species were found abundantly, three were rarely isolated. Neither of the abundant species produces sporangia and both have very small oospores. Of the rarer species, two have filamentous sporangia and all three have rather large oospores.

Botanical Journal of the Linnean Society, Volume 91 Issue 1-2, Pages 297 - 317