POACEAE. 



15 



Tanicle ovoid, the branches wide-spreading at maturity. 

 Panicle oblong, the branches erect. 

 Innovations extravaginal, the long stolons stout and scaly : 



spikelets oblique to the pedicels, the apex decidedly 



curved, hence inequilateral. 



VI. DlCHOTOMA. 



Blades of the stem-leaves long and narrow, linear and 

 narrowed at both ends, very different from the 

 early basal ones. 

 Leaf -blades erect. 



Primary leaves of the stem with blades usually less 

 than 4 mm. wide, from 25-50 times as long as 

 broad. 



Primary leaves of the stem with blades exceeding 

 4 mm. in width, 20 times as long as broad 

 or less. 



Stems simple, or sometimes sparingly branched 

 at the nodes : plants usually bright green : 

 hairs on the leaf-sheaths reflexed. 

 Stems at length repeatedly dichotomous- 

 branched, forming dense mats : plants 

 grayish green : hairs on the leaf-sheaths, 

 if any, ascending or appressed. 

 Spikelets broadly obovoid, about 2 mm. long, 



obtuse. 



Spikelets obovoid, about 3.5 mm. long, acute. 

 Leaf-blades widely spreading. 



Blades of the stem-leaves not long and narrow, usually 

 lanceolate to ovate-lanceolate, sometimes short and 

 linear. 

 Stems simple, or rarely a little branched at the lower 



nodes, forming dense tufts. 

 Leaf-sheaths hirsute. 



Leaf-sheaths glabrous, excepting the ciliate margin ; 

 blades strongly and beautifully ciliate on the 

 margins, otherwise glabrous. 

 Stems finally branching at the upper nodes, often 



repeatedly branching. 



* Middle leaf-blades of the main stem less than 

 1.5 cm. in width, usually less than 1 cm. 

 wide, the base rounded or truncate, some- 

 times in the broadest ones cordate. 

 t Leaf-sheaths glabrous or puberulent, the lower 

 ones sometimes with a few scattered long 

 hairs, the margins often ciliate. 

 Stem-nodes barbed. 

 Stem-nodes naked. 

 Spikelets glabrous. 



Spikelets less than 1.5 mm. long 

 Spikelets about 2 mm. long. 

 Spikelets pubescent. 



Spikelets less than 2 mm. long. 



Leaf-blades ciliate for at least % 



their length. 



Panicle ovoid : spikelets few, 

 1.75 mm. long: leaf-blades 

 small. 



Panicle oblong: spikelets nu- 

 merous, 1.3 mm. long : leaf- 

 blades large. 



Leaf-blades naked on the margins, 

 or sometimes with few long 

 hairs at the very base. 

 Larger stem-leaves with blades 



8-15 mm. wide. 



Larger stem-leaves with blades 

 rarely over 6 mm. wide. 

 Leaf-blades with broad car- 

 tilaginous thickened 

 white margins. 

 Stem with the upper 

 portion naked, the 2 

 leaves below the 

 middle. 



9. P. agrostoidea. 

 10. P. condenaum. 



11. P. ancepa. 



12. P. glabrifolium. 



14. P. laxiflorum. 



15. P. neuranthum. 



16. P. fusiforme. 

 28. P. equilaterale. 



14. P. laxiflorum. 

 13. P. polycaulon. 



19. P. aubbarbulatum. 



23. P. caeruleacena. 

 17. P. Nashianum. 



17. P. Nashianum. 

 24. P. erectifolium. 



24. P. erectifolium. 



21. P. albomarginatum 



