450 Key to the System of 



RESTXO. 



1914. Stems much compressed. 



Seldom tall ; stems undivided ; leaf -stalks .closely clasping, 

 only partly open, occasionally bearing a short leaf, some- 

 times along the stem undeveloped ; spikelets in a simple 

 panicle or raceme, rarely reduced to two or one ; floral 

 bracts pointed ; sepals, petals and stamens two each ; 

 anthers pointless ; styles disconnected ; fruit two-celled ; 

 seeds whitish. R. complanatus. 



Stems cylindrical 1915 



1915. Stems producing repeatedly divided branchlets. 



Often tall and robust ; sterile branches bearing numerous 

 minute leaves, mostly fascicular-crowded ; spikelets very 

 numerous in a generally elongated panicle, from ellipsoid- 

 ovate to globular, of both kinds uniform ; bracts shining- 

 brown, fine-pointed ; sepals and petals of the staminate 

 flowers three, of the pistillate flowers two ; stigmas two ; 

 fruit very small, often only tardily opening ; seeds turgidly 

 ovate, colorless. R. tetraphyllus. 



Stems branchless ... .. ... ... ... 1916 



1916. Leaf-stalks closely clasping. 



Rather tall, slender ; stem-leaves seldom developed and 

 then extremely small, setular, appressed ; leaf-stalks rather 

 short ; spikelets usually numerous, from ellipsoid-ovate to 

 globular, the staminate smaller; floral bracts brown, 

 transparent, often finely pointed ; sepals and petals of the 

 staminate flowers three, of the pistillate flowers two ; 

 stigmas two ; staminodia absent ; fruit minute, roundish, 

 slightly pointed. R. gracilis. 



Leaf-stalks laxly clasping. 



Alpine, somewhat tall ; leaf -stalks without even rudimentary 

 leaves ; spikelets several or few, seldom two or solitary, 

 racemous or spicate ; bracts deep-brown, pointed ; sepals 

 and petals of the staminate flowers three, of the pistillate 

 flowers two ; staminodia present ; style obliterated ; fruit 

 two-celled. R; australis. 



LEPTOCARPUS. 



1917. Staminate spikelets many, comparatively small. 



Often tall ; stems almost greyish, seldom divided ; leaf -stalks 

 closely clasping, terminating in a deciduous tender mem- 

 brane ; leaves quite rudimentary or absent ; staminate 

 spikelets amply paniculate ; stamens very short ; pistillate 



