This slide contains a variety of English Freshwater diatoms. I have provided higher resolution images of many of these below. In some cases the names have changed from what is listed, as the diatoms were reclassified over the years. The slide is in good condition, but as is often the case, some of the diatoms are better specimens than others which are broken, worn, or contaminated. In some cases, the identification is uncertain, either as indicated on the list, or in my opinion; these are indicated with a (?) on the images below. At the time this slide was produced, scanning electron microscopes were not commercially produced, so exact identification was not possible for some diatoms whose classification depends on structures not resolved with the light microscope. Commercial SEMs became available about 1965. In most cases, N.I.C. or oblique illumination was used. Sometimes dark ground illumination was superior, but the best imaging result varies from species to species and in some cases, even between examples of the same species. In some cases, the names have changed

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