This volume contains three contributions, two of which are shorter notes
A synopsis of the genus Orthotrichum Hedw. (Musci, Orthotrichaceae)
The genus Orthotrichum comprises, after the revision summarised in this paper, 116 species and 11 varieties distributed in 7 subgenera. This subdivision is mostly based on peristome evolution and it is presented here for the first time together with a cladogram showing the relationships between the infrageneric categories. Twenty new species and 3 new varieties have been described. The status of 6 species has been changed, 6 other new combinations have been made, and 122 names have been reduced to synonymy. Illustrations of 88 species and 7 varieties have been prepared. Orthotrichum species are either corticolous or saxicolous. They are distributed throughout the world from the Arctic to the Antarctic only avoiding the very wet areas of the tropics and the deserts of Africa and Asia. The genus is considered to have been differentiated on the intact Gondwanaland continent in Triassic-Permian times about 180-300 million years ago, but with major speciation taking place 80-100 million years ago in the Cretaceous. The present paper summarises what is known about the history, morphology, cytology, ecology and geographic distribution of the species. A key to all species and varieties recognised is presented as well as a synopsis of the taxonomic arrangement of these in subgenera and sections. The geographic distributions of the infrageneric categories are illustrated by maps. Four appendices are provided: I, listing recognized taxa with information on systematic position and geographic distribution and references to illustrations; II, listing species for which name or rank have been changed since the publication of Index Muscorum; III, listing species for which no type material has been located, and IV, listing taxa published since Index Muscorum.
The genus Orthotrichum Hedw. (Musci) in Hawaii
The genus Orthotrichum (Musci, Orthotrichaceae) is represented by 6 species in Hawaii. The species are restricted to the young islands in the archipelago, Hawaii, Maui and Oahu. They are thought to have reached these islands fairly recently by wind dispersal.
Notes on some species of Orthotrichum Hedw. (Musci) from Europe, the Caucasus and North Africa
Reports on the study of type material, suggesting taxonomical changes for some European, Caucasian and North African species.