THE BRIGALOW SCRUB 179 



of the Egyptian Sudan extending at the foot of Abys- 

 sinia. Accordingly, its appearance and mode of life 

 offer a striking resemblance to the thorn-bushes of 

 those regions. 



The scrub derives its name from its chief component, 

 the Brigalow acacia, a shrub or small tree with hard, 

 grey, sickle-shaped leaves, and makes a true acacia 

 thornwood. Apart from this, which is very intolerant 

 of other trees, there are two trees of the same family, 

 and a few other tall shrubs, the most characteristic 

 of which is the sandal-wood or dog-wood. The smaller 

 plants and woody perennials gather round the centres 

 formed by the tall shrubs, and often make up impene- 

 trable thickets. Grass is very scanty, but herbs with 

 bright flowers— the African marigold and the scarlet 

 pimelea — relieve with their gaudy colours the prevailing 

 shimmering silvery-grey tone. 



The thornwood becomes more scattered towards the 

 dry interior, and passes into an acacia semi-desert, but 

 towards the east, and on moister soils, it invades the 

 savana and passes to a park-prairie with grass-glades. 

 The scrub and the grass, however, never intermingle. 

 The thorny bush advances in the midst of the swards 

 with an unbroken, impenetrable front, and, untouched 

 by cattle or sheep, slowly claims the grass expanses 

 which have been exhausted by excessive grazing. 



The Mallee Scrub belongs to the half-arid interior of 

 the southern and south-western portions of Australia, in 

 a warm temperate climate. The impression given by 

 a Mallee landscape is one of extreme monotony: 'A 

 boundless, waving sea of yellowish-brown bushes. In 

 the far distance is the blue outline of an isolated hill or 

 a granite top. Otherwise the uniform dark-brown circle 

 of the horizon remains unbroken, silent and motion- 



N 2 



