V Discussion J. Dell & R.A. How The Youanmi-Leonora Study Area is situated north of the mulga-eucalypt line as defined by Beard (1980). Consequently, the majority of plant species are those with a broad distribution in the Eremaean Botanical Province. A southwestern influence is evident in some areas of Broad Valley where the overstorey of Callitris columellaris sometimes attained a height of 7 metres. The Youanmi-Leonora Study Area has examples ofall 10 Landform Units present in the Eastern Goldfields. The most extensive unit is Broad Valley and is usually dominated by various Mulga (Acacia aneura) associations with an ephemeral Asteraceae assemblage after good rains. In areas receiving run-on from heavy rains the Mulga was noteworthy for its height and density and also for the presence of many more shrubby understory species. Spinifex (Triodia basedowil) occurred on more sandy soils of Broad Valleys. There are some important outliers of arid Sandplain containing Eucalyptus gongylocarpa/ Triodia woodlands in the Study Area. Grazing has had a major impact throughout much of the Study Area and has had severe effects on the vegetation (Brockway 1959). In general the lower shrub strata have been reduced or eliminated and soil compaction and rapid run-off are obvious. The herpetofauna of the Study Area is moderately rich with 3 species of amphibian and 43 species of reptiles. Gecko and skink lizards dominate the herpetofaunal with a total of 24 species. A small area of Sandplain had the richest herpetofaunal assemblage with 17 species. All species were within their previously known range and no undescribed species were collected. The 78 species of bird recorded is comparable to the number in other Mulga­ dominated Study Areas in the Eastern Goldfields. Although the number of non­ passerine species was only about half the passerine species, the non-passerines dominated the area numerically. This was in marked contrast to other Study Areas of the Eastern Goldfields. The high number of non-passerine granivores compared to elsewhere in the Eastern Goldfields is supported by the presence of stock drinking troughs and the long-term persistence of seed after heavy rains. The most notable feature ofthe mammal fauna was the six species ofsmall dasyurids with four species in the genus Sminthopsis. This diversity in one genus was not reflected elsewhere in the Eastern Goldfields. The low abundance ofall species of mammals was a consequence of the series of years with below average rainfall prior to and during the study. The Study Area has no conservation reserves. Most ofthe area is pastoral lease except for some unreserved Crown Land in the southwest of the Study Area. Although the south west is dominated by a single Landform Unit (Sandplain) a reserve here would include a number ofvegetation types. In conjunction with adjacent Landform Units this would provide a conservation reserve of substantial size. 33 VI Acknowledgements We are grateful to the Curator ofthe Western Australian Herbarium, OrJ. W.Green, for making available facilities generally, and we record our appreciation to K.F. Kenneally and the technical staff, for aiding the processing of System II specimens. Assistance with identification of plants was provided by staff of the Western Australian Herbarium: T.E.H. Aplin (Poaceae), J. W. Green (Micromyrtus and Thryptomene), K.F. Kenneally (Halgania), N.S. Lander (Lawrencia and Olearia), T.D. Macfarlane ( Wurmbea and Poaceae), N. G. Marchant (Chamelaucium and Drosera), B. R. Maslin (Acacia), G.Perry (Rhamnaceae and introduced species), B.L. Rye (Pimelea) and P.G. Wilson (Asteraceae, Chenopodiaceae and Rutaceae). Appreciation is also expressed to M.I.H. Brooker of CSIRO, Perth (Eucalyptus), R. Carolin (Goodeniaceae) and P. Weston (Persoonia) of University ofSydney and H.J. Hewson (Brassicaceae) of Bureau of Flora and Fauna, Canberra, Hj. Eichler (Zygophyllum) and J.G. West (Dodonaea and Calandrinia) of the Australian National Herbarium, Canberra, B.J. Conn (Lamiaceae) and P.S. Short (Asteraceae) of Royal Botanic Gardens, Melbourne, R.J. Chinnock (Eremophila and Aizoaceae) and H.R. Toelken (Crassula) of State Herbarium ofSouth Australia, D.J. McGillivray (Grevillea) of Royal Botanic Gardens, Sydney, M. Trudgen of Perth (Baeckea), and D.A. Cooke of Melbourne (Centrolepis). We are also grateful to G. Barron, K. Cashin, D. Fox-Gray, J. Henry, T.F. Houston, K. Kelly, J. W. Stuartand B.O. Wellington for assistance with field data collection. G.M. Storr and D.J. Kitchener helped with identification of reptiles and mammals. C.E. Blumer, E. Hallam, M. Green, L. Peters and B.O. 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