The myxomycetes have been collected and studied for more than three-and-a half centuries, and during this period, they have been variously classified as plants, animals, or fungi. Numerous individuals have contributed to the body of information currently available for these organisms. Prominent among these were the two Listers (Arthur and Gulielma) in Europe and George Martin and Constantine Alexopoulos in the United States. This chapter represents an effort to highlight the contributions of these and other workers and to provide a brief overview of the studies of myxomycetes carried out in various countries and regions of the world. Early studies of myxomycetes were based entirely upon their morphology, but a more modern multidisciplinary approach, which includes the application of the techniques of molecular biology, is now being used to investigate these organisms.

A new species of corticolous myxomycete, Licea margaritacea, is described from bark of sycamore and Norway maple trees growing by the River Nith in Dumfries.

The occurrence of the American Horse Chestnut mildew, Uncinula flexuosa, is reported from Europe, including Great Britain, for the first time (New British Record 210). A key is provided for the identification of powdery mildews on horse chestnuts in Europe.

Summary Summary Fourteen species of Exobasidiales are reported from Scotland with notes on their ecology, distribution and the effects on their hosts, which are mostly members of the Ericaceae.

Summary. Sixty bark samples were collected from living trees at seven sites in different ecological regions of Belize and cultured in moist chambers. 37 species of myxomycetes were isolated all of which are new records for Belize. Twelve species are new records for Central America and two, Licea erectoides and Paradiacheopsis rigida, are new to the western hemisphere. The rare Physarum tropicale is recorded for the first time outside Mexico. samples of bark from living trees in several areas of Belize, representing different ecological regions of the country. Sixty samples were collected, later placed in moist chambers in Chester using the standard method devised by Gilbert & Martin (1933). The cultures were maintained for a minimum of three months and in some cases, e.g. Willkommlangea, for up to six months. This allows the slower growing casual species to develop and thus assures a wider range of species is identified from the region. Results are reported here. A total of 37 species were obtained, all of which represent new records for Belize. All specimens are preserved in Herb. B. Ing. The tropical climate and diversity of landscape of mainland Belize provide an environment for some 4000 species of native flowering plants, including 250 species of orchid and approximately 700 species of native trees (Mallan 1993). Belize is divided into several climatic zones which are governed by rainfall, and the still extensive forests form four distinct communities - pine-oak, mixed broad-leaf, riveraine and cohune palm forest. Belize is bordered by off-shore fringing coral reefs and cayes, ranging in size from small coral islands awash at high tide to substantial islets with mangroves and coconut palms. Myxomycetes from Belize have received little study, the few recorded species being included by Farr (1976). Distributional comments given below are based on this reference and, for Mexico, additionally on Hernandez-Cuevas et al. (1991).

Summary Sixteen species of snowline myxomycetes have been recorded from Scottish mountains. The history of these records and the ecology of these taxa are discussed. Heavy grazing is suggested as a reason for the paucity of alpine myxomycete communities in Scotland, compared to the Alps, and further studies on ledge communities are advised.

Tulostoma niveum is considered to be threatened in world terms and is confined to a small number of sites in Sweden and Finland and a single site in north-west Scotland. This paper reports on changes in this Scottish population since its discovery in 1989, and on the phenology of fruiting in 1996. In Scotland all new fruit-bodies appeared between July and October, in contrast to Sweden where fruiting occurs in late autumn and winter. Reasons for this difference are discussed.