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I mirmte hooked thorns scattered over the surface of the branches, 
which themselves are green and adapted to perform the function 
of leaves. The woody fibres of the stem spread out to foim a 
thin layer under the cuticle, and inside this rigid tissue a wide 
space is occupied by a spongy pith, adapted to hold moisture. 
(Plate IV. Fig. 2.) 
Acacia, alata R. Br. 
A Leguminous shrub of the Sub-Order Mimoseae. Along 
with four others, it forms the Series Alatae of the genus Acacia, 
which are peculiar to Western Australia. Not only are the 
leaves in this Series reduced to phyllodia, but these enter into 
the formation of the stem and branches, providing them with 
wings, and having only their tips free. (Plate V.) 
