In this monograph sexual reproduction in fungi, algae, archegoniates and higher plants is discussed in a comparative way. Much attention is devoted to a terminology which is generally applicable throughout the plant kingdom. After a general introduction, haplontic, diplontic and haplo-diplontic organisms are described in succession. In these parts, a distinction is made between genetical and modificatory (phenotypical) sex determination. The first term is used when the sexes (or mating types) are distributed in a mendelian ratio among the progeny of a zygote, whereas the second term applies to those cases where cells with the same genetic information may express either raaleness or femaleness, depending on the circumstances. Of course, in both cases sexual differentiation is genetically determined, and for that reason the terms seem hardly appropriate. Somewhat confusing may be the association of modificatory sex determination with the now obsolete concept of “relative sexuality”, which means that a gamete may behave as male or female, depending on the partner. The book also includes a chapter on parasexual phenomena in prokaryotes and a discussion on the evolution of sex. The only comprehensive treatise covering this field is volume 17 of the Encyclopedia of Plant Physiology, which appeared in 1967 and contains 874 pages. It is only natural that the author has not succeeded in producing a small book with the same coverage. The different systems are dealt with in a descriptive way. The text is rather compact and the inclusion of more figures might have increased its clarity. For a subject like this, which calls for a multidisciplinary approach, many physiological and genetical aspects have been completely neglected or are only briefly described. The author refers only rarely to recent literature, which will particularly disappoint readers who want to keep abreast of major experimental advancements in this area.