|Abstract||Prostrate hairy herbs. Leaves opposite, paripinnate, mostly anisophyllous; stipules present. Flowers actinomorphic, 5-merous, bisexual, solitary on pseudo-axillary peduncles, white or yellow. Sepals 5, free, imbricate, persistent or caducous. Petals 5, free, patent, imbricate, fugacious. Disk present. Stamens 10, subequal or unequal; anthers dorsifixed. Ovary superior, sessile, hairy, 5—12-lobed, 5—12-celled; style short and thick, with 5—12 decurrent stigmas; cells with 3 or more ovules. Fruit 5-angled or 5—12-winged; cocci partly abortive, spinous or tuberculate, indehiscent with 3-5 superposed seeds separated by septa.|
Distr. & Ecol. Ca 20 spp. difficult to delimit, specially developed in the dry regions of Africa and Australia. In S. Africa the spinous fruits adhere to the wool and feet of sheep (‘hoof-burs’) and are a nuisance. The family has about 26 genera, of which 12 monotypic, and ca 250 spp., mostly of warm dry countries. In Malaysia one genus and one species.