404 THE HORN EXPEDITION TO CENTRAL AUSTRALIA. as the result of personal knowledge of the country he proposes to shift the boundary to the latitude of Engoordina. To the north of this is a tableland of Ordovician sandstone eroded in long parallel east and west valleys of varying width. This area Prof. Tate terms Larapintine from the native name Larapinta of the upper and middle Finke river. We gather from the Eeport that the first botanical exploration of this region was by J. Macdouall Stuart, who collected during his travels from the Finke River to the McDonnell Range in 1860-62. The plants were determined by Baron von Mueller, and an enumeration of them was published as an appendix to the Journals of J. McD. Stuart, London, 1864. Ten years later Ernest Giles geographically explored the Larapintine region to the westward of the Finke River, and made extensive botanical collections ; these were likewise worked out by Baron von Mueller, and published as an appendix to Mr. E. Giles' Geographic Travels in Central Australia (1872-74). It contains the names of 254 species, of which 114 belong to the Larapintine flora. Contemporaneously with Giles, W. 0. Gosse crossed the western confines of the Larapintine region in his traverse from Central Mount Wedge and Mount Liebig to Mount Olga ; and the Rev. H. Kempe, of the Mission station at Hermannsburg, has also made successive collections in the same region, the results of which have been published in the Transactions of the Royal Society of South Australia, vol. iii. p. 129, 1880, and vol. V. p. 19, 1882. In 1889 Mr. Tietkens traversed the northern part of the Larapintine region from Alice Springs to its western limit, and added fifty-eight species, including five new to science, to the Flora {Trans. Boy. Soc. S. Austr. xiii. 94-109, 170-171, 1890). Other smaller collections have been made, the novelties having been from time to time published by Baron von Mueller. The number of species known for the Larapintine region previous to the advent of the Horn Expedition was 502 ; this has now been increased to 614, the additions including eight new species — Acacia Cowleana Tate, A. frumentacea Tate, Didisciis GillencB Tate, Wedelia Stirlingi Tate, Ooodenia Horniana Tate, G. Larapinti Tate, Elacholoma Horni F. v. M. & Tate (a new genus of Scrophularinece), Xanthorrhcea Thorntoni Tate — and six- teen new for South Australia. The dominant feature of the Central Eremian region is the pre- valence of salsolaceous plants, especially over the stony places and loamy flats ; in the Larapintine region they are replaced by grasses, and of these a species of Triodia (porcupine grass, or, incorrectly, "spinifex" of explorers and residents) dominates sandy ground and the sterile slopes and tops of the sandstone table-lands. The arboreous vegetation is represented by Casuarina Decaisneana (desert oak), Grevillea striata (silky oak), Br achy chiton Gregorii, Ficus platypoda, Eucalyptus terminalis, E. Oldfleldii, Canthiurn lati- folium, Livistona viaria, Encephalartos Macdonnellii, and others which are either restricted to the region or do not pass beyond its southern boundary. Acacia Famesiana, Atalaya hemiglauca, Eucalyptus tessellaris, and E. gamophylla are prevalent, though
