The first edition of this book was published in 1976. In this second, revised edition especially the chapter on Deuteromycetes has been changed and extended with more examples. The book is an introduction into the field of thallophyta, intended to be used as a guide for more extensive (‘classical’) university courses on this group of cryptogams. It is well-illustrated with many drawings, photomicrographs, and schemes of life-cycles. In the theoretical part the principles of reproduction cycles are discussed. The part on technical methods gives a selection of cultural methods and microscopical staining procedures. The major part of the book is devoted to practical information on the main classes, orders, and families of the thallophyta. Appropriate objects are listed, certain tasks for students are set, and information is given on the structures to be observed.