64 THE FAMILIES OF CYCADS AND THE ZAMIACEAE OF AUSTRALIA. By L. A. S. Johnson, National Herbarium, Royal Botanic Gardens, Sydney. (Four Text-figures.) [Read 25th March, 1959.] Synoiisis. The general classification of the Cycadales is reviewed and grounds are put forward for the recognition of three families: Cycadaceae {Cycas), Stangeriaceae, fam. nov. (Stangeria) and Zamiaceae (remaining genera). A taxonomic revision of the Australian members of the Zamiaceae is provided. Three 1 genera, all endemic, are recognized: Lepidozamia Regel (2 spp.), Macrozamia Miq. (14 spp. : 6 in sect. Macrozamia, 8 in sect. Parazamia), and Bowenia Hook, ex Hook. f. (2 spp.). New taxa are described and new combinations made as follows: Lepidozamia hopeites (Cookson) L. Johnson (fossil species), Macrozamia communis, M. diplomera (F. Muell.) L. Johnson, M. lucida, M. stenomera, M. pauli-guilielmi W. Hill and F. Muell. sspp. plivrinervia and flexuosa (C. Moore) L. Johnson. The name M. spiralis (Salisb.) Miq. is shown to be correctly applied to the species known as M. corallipes Hook. f. The species known as M. spiralis in Queensland and New South Wales are the n. spp. M. lucida and M. communis respectively. Keys and discussions are provided for all taxa and the very confused synonymy is reviewed and' clarified. Introductory. This study has arisen out of the necessary revision of the New South Wales species of Macrozamia for the forthcoming Flora of New South Wales, part 1 (in press). It was clear from the outset, that the specific limits needed clarification and that the nomenclature was in a state of chaos. Moreover, it soon became evident that generic as well as specific concepts were at issue and this in turn led to a consideration of the general taxonomy of the cycads. Part I. The Families op Cycads. General. It has been customary to refer all the true living cycads (universally accepted as the order Cycadales) to a single family, Cycadaceae, variously divided by different authors into subfamilies, tribes and subtribes. Schuster (1932, p. 63) gives a synopsis of these arrangements. Amongst these categories, however, all authors have recognized a suprageneric taxon including Cycas alone. In recent times only Wettstein (1923) has placed Cycas in a family (Cycadaceae sensu stricto) by itself, grouping the remaining genera as Zamiaceae. The latter family had, however, been established much earlier by Reichenbach (1837), though several cycad genera were then unknown. Taxonomists have a tendency to recognize very inclusive families in the-more unfamiliar groups of plants. The cycads are rather few, they are all very different from other living plants and they are clearly related to each other; consequently most botanists, impressed by this apartness, are content to lump them together and to minimize the differences within the group. Now all taxonomic classification, at least above the specific level, is to a considerable degree subjective as regards the status of admittedly related taxa. To take familiar examples from the flowering plants, the dismembering of the Leguminosae s. lat. into the three families Mimosaceae, Caesalpiniaceae and Papilionaceae must be more subjectively based than the exclusion of Paeoniaceae from Ranunculaceae. In the former case few will deny that the segregate groups have a closer phylogenetic relationship among themselves than any one of them has to other living families; the claim for family status rests on the Proceedings of the Linnean Society of New South Wales, 1959, Vol. Ixxxiv, Part 1.
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