The floristic composition of remnants ofThemeda australis grasslands from basaltic areas of western Victoria was described using methods employed by the Ziirich-Montpellier school ofphytosociology. Most sites sampled were managed by either regular burning (rail sites) or grazing, or were not subject to any regular management practices (roadside sites). Rail sites contained relatively open, species-rich vegetation with a smaller proportion of introduced species than the other two types of site. Grazed paddock sites contained relatively open, species-poor vegetation, whilst roadside sites contained relatively dense, species-poor vegetation. Sueh site differences appear to be related to the effect of management practices upon the competitive ability of T, australis and to species tolerance of them.

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A group of flowering plant species is known to germinate in less than 24 h from imbibition, but this phenomenon is often overlooked in the current literature. Here, I review this topic by searching the literature published since 1967 and listing the 28 most detailed cases found. Of these, 20 are species of Amaranthaceae (all formerly treated as Chenopodiaceae); 15 of these are from the subfamily Salsoloideae, which is characterized by the possession of spiral embryos. The non-chenopods listed are small numbers of species from the families Acanthaceae, Cruciferae, Gramineae (one species) and Salicaceae (Populus and Salix). Seeds of the Salsoloideae contain fully differentiated embryos. On imbibition, the embryo cells elongate and the spiral embryo uncoils and ruptures the thin seed coat. This can occur in as little as 10 min. Nearly all of the families showing very fast germination have small to very small seeds and little or no endosperm. Most species have soft, thin seed coats that imbibe water readily. All are from high-stress habitats, either arid or saline or from active floodplains, where they can rapidly exploit temporarily favourable conditions for germination. They exhibit one of two contrasting germination behaviours, either having seeds which all germinate within a very short time of wetting or having seed persistence whereby small amounts of rain cause germination of small fractions of seed from a long-living soil seed bank. Serious confusion in the literature in the use of the term ‘opportunistic’ is pointed out and clarified.

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Coastal scrub and woodland of varying fire history and variously dominated by Banksia integrifolia, Leptospermum laevigatum and Leucopogon parviflorus were studied using size-class analysis of the dominant species. Transects from L. laevigatum scrub to B. integrifolia woodland were recorded in areas burnt (a) 32 years ago and (bj more than about 80-100 years ago. Post-fire invasion of B. integrifolia by L. laevigatum is described in the younger stands. Only Leucopogon parviflorus shows widespread seedling establishment in the absence of fire. In the old L. laevigatum stands, there is good evidence that this species is dying out and being replaced by L. parviflorus which appears to be the climax dominant in non-Banksia areas in the absence of fire. Although B. integrifoHa seedling establishment is very rare in mature stands, no degenerate Banksia stands were found, so it is not yet clear whether this species is selfmaintained in the absence of fire.• Species nomenclature follows Willis (1972).