MEMOIRS OF THE NEW YORK BOTANICAL GARDEN 4 [Vol. 9, No. 3 



17. Leaf-blades not more than 6 mm wide; petals yellow. 



20. Inflorescence raised above the leaf-sheaths on an evi- 

 dent scape; petals slightly exceeding the sepals. 



1 1. N. serrulata. 

 20. Inflorescence sessile; petals about twice as long as the 



sepals. N. aurea. 



14. Floral bracts entire or subentire. 

 21. Leaf-blades 8-18 mm wide. 

 22. Leaf-blades serrulate. 



23. Inner leaf-blades basally white or rose at anthesis; 



larger leaf-spines acicular. 12. N. colorata. 



23. Inner leaf-blades wholly green like the others; leaf- 

 spines all small, low, and broad. 

 24. Inflorescence conspicuously involucrate with broad, 

 erect outer bracts; petals yellow; sepals 14 mm long; 

 leaves white-flocculose above. 13. N. irtuolucrata. 



24. Inflorescence not conspicuously involucrate, its outer 

 bracts narrow; petals white so far as known; sepals 

 5-19 mm long; leaves glabrous or subglabrous above. 

 25. Sepals 5-8 mm long; inflorescence digitate-globose 

 from several ellipsoid spikes, many-flowered. Ven- 

 ezuela, Amazonian Brazil. N. crispa. 

 25. Sepals 14-19 mm long; inflorescence few-flowered, 

 simple. 



26. Leaf-blades narrowly triangular, not at all nar- 

 rowed at base, 7 cm long, 9 mm wide. Vene- 

 zuela: Duida. N. glauca. 



26. Leaf-blades linear, to 37 cm long and 16 mm 

 wide. 



27. Leaf-blades sparsely tomentulose; floral bracts 



acuminate, pungent. British Guiana. N. angusti folia. 



27. Leaf-blades densely cinereous-lepidote be- 

 neath; floral bracts elliptic, membranaceous. 



14. N. nubicola. 



22. Leaf-blades entire; inflorescence many-flowered; sepals 

 9—10 mm long. 



28. Inflorescence ellipsoid, somewhat longer than broad; 

 leaf-blades 9-10 mm wide, soon glabrous. Amazonian 

 Brazil. N . myriantha. 



28. Inflorescence hemispheric, broader than long; leaf- 

 blades 15 mm wide, the margins lanate. 15. N. lanigera. 

 21. Leaf-blades 2-4.5 mm wide. 



29. Leaf-blades abruptly acute or obtuse; sepals lepidote, 10- 

 11 mm long; petals yellow. Venezuela: Duida. 



N. brachyphylla. 



29. Leaf-blades evenly long-acuminate. 

 30. Sepals 12-14 mm long, entire. 



31. Petals yellow; sepals glabrous; leaf-blades glabrous. 



16. N. pulvinata. 

 31. Petals white; sepals lepidote at the apex; leaf-blades 



lepidote beneath. Venezuela: Duida. N. duidae. 



30. Sepals 6 mm long, denticulate on the keel. 17. N. saxicola. 

 12. Sepals obtuse or subacute, often cucullate. 

 32. Leaf-blades 9-20 mm wide. 



33. Keel of the posterior sepals dilated below the apex. Vene- 

 zuela: Du«da. N. xyridiflora. 

 33. Keel of the posterior sepals linear or gradually narrowed from 

 base to' apex. 



34. Sides of the posterior sepals 1 mm wide, their keels very nar- 

 row; inflorescence few-flowered. 18. N. pauciflora. 

 34. Sides of the posterior sepals 2 mm wide. 



35. Leaf-blades with a pale contrasting median stripe, linear, 



not cretaceous; floral bracts serrulate. 19. N. octopoides. 



