122 Kkllv. Concerning Acacia Phyllodes. Ivoi'^^xxix 



avoiding the glare that robbed their ancestors of their feathered 

 foHage. Another example is seen in A. leprosa, which has 

 only one main vein (or midrib) in the phyllode. It has thus, 

 from the view of recognized true leaves, improved on its near 

 relatives, A. verniciflua and A. montana, which have two 

 veins. A. stricta has also achieved the distinction of phyllodia, 

 with one main venule forming a distinct midrib, and has its 

 secondary venules reticulated, thus having claims to admission 

 to the high society of true leaves. It is a nice question, how- 

 ever, whether two midribs, or veins, or venules, or whatever 

 they might be called, are not better than one. 



Opposed to this theory, or at least inconsistent with it, is 

 the peculiarity of such plants as A. verticillata, A. diffusa, and 

 A. juniperina, particularly the former — a typical gully plant. 

 A. verticillata (or " Prickly Moses," as it is commonly called — 

 a corruption of Prickly Mimosa) produces the finest acicular 

 phyllodes in whorls of five or six, and yet its common habitat 

 is the most moist and sheltered. One would think it would 

 constantly struggle for light and try for the greatest exposure 

 of leaf. It makes one incline to the belief that the parts in 

 which these plants now grow were once arid, and that they 

 had retained the acquired characters when the conditions 

 became entirely changed ; but confronting that theory is the 

 fact that the soft-foliaged bipinnate types grow in the same 

 locality. When, however, we closely examine the whorled 

 phyllodes, we find that they do not form a perfect whorl in 

 that they are not set opposite, but one pair slightly above the 

 other, and often one single phyllode, or perhaps a pair, in a 

 slightly different position still. If we take A. Baileyana, the 

 Cootamundra Wattle, a pinnate type, and strip the pinnae 

 from the leaf-stalks, we find the latter situated in a corre- 

 sponding position. A reduction of the total length of the stem 

 would conceivably happen in such adverse circumstances as 

 would bring about the disuse of the pinn;e. This would bring 

 the leaf-stalks in the quasi-whorled position of those in A. 

 verticillata. Assuming, for illustrative purposes, that A. verti- 

 cillata descended from A. Baileyana, we find the axillary 

 position of the flower-stalk very similar in both, and it takes 

 little imagination to see the racemose inflorescence of the 

 Cootamundra varying to the catkin form in " Prickly Moses," 

 side by side with the change from pinnae to acicular phyllodes. 

 In cultivation the j^hyllodcs of A. verticillata sometimes grow 

 upwards in the form of the spokes of an inverted umbrella. 



Acacias with very small or very narrow phyllodes are small 

 or only moderate-sized shrubs. The pinnate-leaved forms are 

 principally more or less arborescent. In dry, hot parts of 

 Australia the surviving plants would not only reduce their 



