__^ The S outh Australian Naturalist. 135 



climbed up on this roadway, which, used as a track in early 

 days, has later become a gutter for the waters, which have 

 kept its rough, stony surface almost entirely clear of vegeta- 

 tion, the white surface showing up very clearly from the jetty. 

 The whole hill is made up of a particularly hard quartzite, 

 broken up near the surface into blocks of road metal of vary- 

 ing sizes and holding but little soil. The rain that falls is 

 easily absorbed, a small proportaon running down the steep 

 slope, and only a very minute proportion being retained by the 

 scanty soil. Hence the plant growth is that characteristic of 

 a dry region, or of desert conditions, even though the rainfall 

 is abundant, probably over oO inches. Every plant that has 

 established itself on this area must have some special adapta- 

 tion to fit it for suL'h conditions. Many of such plants have 

 dry, prickly foliage, with small leaves, or an absence of leaves. 

 The Hakeas are typical examples, and it is because such plants 

 are so abundant that the whole hill looks so dark when viewed 

 from the plains. The Banksias that grow here are noticeably 

 dark and stunted, and this applies to many, if not most, of the 

 species represented. The gum trees {.Eucalyptus fasciculosa, 

 pink gum. and E. capifeUata, or BlaxlandU) were both 

 stunted in habit on the quartzite. Two other characteristic 

 plants are the Scrub Sheaoak [Casuarina distyla) and the Yacca 

 (Xanthorrhoea quadrangulata). The top of the hill is a fairly 

 level tableland, on which the soil is deeper and more retentive. 

 Here the gum trees form a 'fairly thick scrub, with bushes of 

 pink, red, and white heath (Epa<:ris impressa) in full bloom. 

 Several of the party climbed to the fop, and a few went on to the 

 further summit, 1,.'540 feet above sea-level, and over 1,000 feet 

 from the point at which the party left the char-a-banc. The 

 descent was, if not as difficult, almost as trying as the ascent, the 

 stony nature of the ground and the loose boulders making it very 

 fatiguing. The leader, Mr. E. H. Ising, was successful in find- 

 ing a plant of the somewhat rare orchid, Pterostylis vittata, one 

 of the greenhoods, in full bloom. This orchid has a sensitive 

 tongue, which springs up suddenly when an insect alights upon 

 it, thereby dusting the insect with pollen, to be transferred to 

 the sticky^, receptive surface of the next flower visited. The 

 dainty little mosquito orchid, Acianthus exsertus, and a green- 

 hood, Pterostylis refiexa, were also taken. A little heath-like 

 plant, Astroloma conostephioides, was in full flower, as well as 

 the little bushes of sweet-smelling Cryptandra foment osa. The 

 delicate blue flowers (somewhat resembling violets) of the honey- 

 bush, Ilyhanfhus florihundus, were plentiful. The grasstrees, 

 Xanthorrhoea qiiadrangidata, are abundant on the hillside, and 

 a few X. semiplana were seen. The trees were found to be 



