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Nuytsia Vol 7, No. 2 (1990) 
Utilizing this material the populations were found to differ significantly in habitat, habit, the 
angle of the leaves to the stem, shape of the flower, perianth, pistil and pollen presenter. These 
characters are occasionally discernible on herbarium material, but form a major character sequence 
readily obtained by field observations. Characters of habit, leaf presentation, the form of the 
perianth, pistil and pollen presenter are constant and significant characters in this complex and 
elsewhere in the genus Grevillea (author, pers. obs.). These differences are difficult to describe but 
are presented in illustrations. 
Results 
Field surveys carried out in 1986/87 showed that populations occurred in three disjunct regions, 
namely Swan Plain, Scott Plain and Blackwood Plateau. Tabulation of a wide range of vegetative 
and floral characters (Table 1) clearly demonstrates that the Blackwood Plateau populations are 
markedly different from the other plains populations. These differences are reinforced by habitat 
differences (see under species descriptions) and floral characters (Figures 1 and 2). 
There are no intermediate populations, and populations of Grevillea brachystylis and Grevillea 
bronwenae, occurring within 100 metres of each other on Queen Elizabeth Road, maintain the 
differences. 
Clearly the Blackwood Plateau populations should be given specific status. The two disjunct 
coastal plain forms differ in minor characters (habit, colour of pollen presenter) and are thus given 
subspecific status. 
Taxonomy 
1. Grevillea brachystylis Meissn. in Lehm., PI. Preiss. 1: 538 (1845); 252 loc. cit. 2: Type: 
Mocloy’s Plain, Sussex District, 20.12.1839, J.A.L. Preiss 714 (holo: NY, photo seen). 
Much branched, prostrate or decumbent to erect shrub with branches to 2 m long. Stems 
slender, shiny red with current years growth almost glabrous except at ends, ± 1 mm wide. Leaves 
erect, linear-lanceolate, 64-87 x 8-10 mm; margin recurved; upper surface smooth green; under 
surface densely hairy- white; apex acute or pungent with a black point 0.5-1 mm long. Inflorescence 
axillary, 6-7 flowered. Peduncle 4-6 mm with long, densely pubescent with short silver hairs. 
Basal bract of inflorescence lanceolate-ovate, brown; apex acute, ± 7 mm long, densely hairy. 
Bracts! bracteoles subtending flowers normally 3, imbricate, ovate; brown, 3-4 x 5 mm, pubescent, 
persistent; apex acute. Pedicel 3.5-4.5 mm long. Perianth red, slightly saccate, 7-8 mm long; limb 
6 mm long, sparingly hirsute. Pistil 7-9 mm long; stipe 3 mm long; ovary 0.5 mm long. Pollen 
presenter 3-4 mm long, red or pale purple. Ovary densely hairy. Nectary yellow, c. 1 mm long, 
producing copious nectar. Capsule 10-11 mm long, sparsely hairy with retained style. Seed elliptic, 
supervolute, ± 7 mm long, brown; eliasome white, ± 2 mm long. Figure 1. 
The species contains two subspecies. 
la. G. brachystylis Meissn. subsp. brachystylis 
A much branched, prostrate or decumbent shrub with branches to 60 cm long. Pollen presenter 
red. 
Specimens examined. WESTERN AUSTRALIA: Busselton, 27 Sept. 1944, C.A. Gardner s.n. 
(PERTH); Yoongarillup, R.D. Royce 3806 (PERTH); Busselton area, (33° 40’ S, 115° 35’ E), 
A.R. Fairall 2557 (KPBG); 3 km E of Busselton, S. Paust 117 (PERTH); Ruabon, G.J. Keighery 
1022 (PERTH); Fish Road Nature Reserve, G.J. Keighery 9484 (PERTH). 
