THE FLOEA OF THE NOBTHEBN TBBEITOEY. 123 



Leaves all or mostly reduced to flat terete or subulate phyllodia or minute 

 scales without leaflets. (Phyllodinece). 

 Flowers in globular heads. 



Phyllodia none or reduced to minute scales. — IV. Calamiformes. 

 Phyllodia (either small and toothlike or vertically flattened or 

 elongated), decurrent on or continuous with the branches. 



Branches flat or 2-winged by the decurrent phyllodia. — 



I. Alatae. 



Branches 3-winged or the phyllodia (usually pungent) very 

 shortly or scarcely decurrent, but not articulate. — 



II. Continuse. 



Phyllodia articulate on the stems, at least when old. 

 Phyllodia rigid, tapering into pungent straight points, usually 

 narrow or short, not whorled. — III. Pungentes. 



Phyllodia linear-subulate, terete or tetragonous rarely 

 slightly flattened, obtuse or with incurved or innocuous 

 points, not whorled. — ^IV. Calamiformes. 



Phyllodia terete or slightly flattened, usually short, 

 all whorled or crowded and irregularly whorled or 

 clustered. — V. Brunioidese. 



Phyllodia vertically flattened, broader than thick, obtuse 

 acute or with incurved or innocuous points. 



Phyllodia 1 -nerved, the veins pinnate, reticulate or 

 rarely 1 or 2 secondary small nerves from the base 

 on one side of the midrib. — VI. Uninerves. 



Phyllodia with 2, 3 or more parallel nerves. — 

 VII. Plurinerves. 



Flowers in cylindrical or oblong spikes. 



Phyllodia rigid, tapering into pungent points. — ^III. Pungentes. 

 Phyllodia obtuse or with a callous, innocuous or hooked 

 point. — VIII. Juhflorae. 



Leaves all bipinnate. Flowers in globular heads or rarely in spikes. — 

 (BipinnatoR.) IX. Gummiterse. 



Div. I. Phyllodinece. — Leaves mostly phyllodineous without leaflets. 



Series I. Alaim. — Phyllodia bifariously decurrent, forming two opposite 

 wings to the stem, the free part short, broad, and acute, or rigid and pungent- 

 pointed. Flowers in globular heads, on axillary simple peduncles rarely ap- 

 pearing racemose by the reduction of the flowering branches. — 9. A. 

 bossiseoides. 



Series II. Continuce. — Phyllodia narrow, rigid, rapering into a pungent 

 point, continuous with the stem and shortly and trifariously or irregularly 

 decurrent. Flowers in heads or spikes on axillary simple peduncles. — 45. A. 

 Peuce. 



Series III. Pungentes. — Rigid shrubs, branches in some species spinescent. 

 Phyllodia articulate on the stem, rigid, tapering into pungent points, subulate, 

 linear or lanceolate, or rarely none. Flowers in heads or spikes on axillary 

 simple peduncles. 



A. Plurinerves. — Phyllodia 2 or more nerved, or terete and nerveless. 

 Heads globular. — 46. A. phlebocarpa. 



B. Uninerves. — Phyllodia 1 -nerved. Heads globular. — 44. A. patens. 



