Planktonic, benthic, and epiphytic samples were collected and their diatom assemblages investigated by the authors from different locations in the lower Gordon River estuary and some adjacent lakes. Two of these lakes are meromictic, one vacillates between meromixis and holomixis, and the last one is holomictic (though might have also been meromictic in the past). As the authors think, these lakes and another one of their sampling sites from the estuary, a back-water, represent different developmental stages of meromictic lakes. The authors used Detrended Correspondance Analysis to ordinate their data; the book presents diagrams showing the grouping of the sample sites and of the found diatom-taxa. In the introduction these results are discussed shortly, and in the taxonomic part a species list is presented, that contains 272 taxa. Taxonomic (e.g. valve dimensions, striae density) and ecological (particularly about salinity tolerance) data are given about them, and also their distribution in the collected samples can be read here. Of the most taxa there is also a light- or electron-micrograph at the end of the book. Besides these floristical data the book also presents the results of the diatom investigations of a 17 m long core extracted from one of the two meromictic lakes. Comparing the found assemblages to those found in their recent samples, they could reconstruct the development of the place from perhaps a channel to a lake and also the occurrence of meromixis.

All in all, the book should be of interest not only for those that investigate Tasmania's diatomflora but also for algologists interested in taxonomy and / or palaeolimnology and anyone else, as the investigated sytem, the estuary and the adjacent lakes, is really interesting and rare.

B. Beszteri

Acta Botanica Hungarica 42 (1-4), 1999/2000