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MEMOIRS OF THE NEW YORK BOTANICAL GARDEN 



[VOL. 10 



Key to the Species 



1. Inflorescence usually decompound ; pedicels erect to slightly spreading, never re- 

 flexed; caruncle small, 0.4 mm long or less, obtuse, erect. 3. L. johnxtonii. 

 1. Inflorescence simple or compound; pedicels erect to reflexed; caruncle more than 

 0.4 mm long, erect or hooked. 

 2. Leaf with a small mucronate projection extending from the callose tip; flowers 

 3.5-4.5 mm long. 



3. Caespitose, or with short rhizomes; inflorescence compound; pedicels erect to 

 slightly spreading; fruit shorter to just equalling the perianth; caruncle erect, 

 less than 0.8 mm long. 2. L. forsteri. 



3. Stolonif erous ; inflorescence commonly simple, pedicels spreading to reflexed; 



fruit exceeding the perianth; caruncle erect to slightly curved, 1-1.5 mm long. 



4. L. luzulina. 



2. Leaf without a mucronate projection on the callose tip. 



4. Plants stolonif erous ; cauline leaves tapering abruptly to the callose tip. 



7. L. rostrata. 



4. Plants stolonif erous or caespitose; the cauline leaves tapering gradually to a 

 callose tip. 



5. Perianth 1.6-2.5 mm long; inflorescence simple to rarely slightly compound; 



pedicels spreading. . 8. L. rufescens. 



5. Perianth over 3.0 mm long; inflorescence usually strongly compound; pedicels 



erect to spreading. 



6. Plants caespitose, occasionally with short rhizomes and stolons, to 3 cm long. 

 7. Plants caespitose; culm leaves 1-3 mm wide, to 4 cm long; perianth 3-4 

 mm long; anthers usually twice as long as the filaments; caruncle about 

 0.8 mm long, curved. 5. L. pilosa. 



7. Plants caespitose or with short rhizomes and stolons; culm leaves 2-8 mm 

 wide, to 7 cm long; perianth 3.5-4.3 mm long; anthers half as long to 

 longer than the filaments; caruncle 1-1.5 mm long, erect or hooked. 



6. L. plumosa. 



6. Plants strongly stolonif erous. 1. L. acuminata. 



1. Luzula acuminata Raf. 



Perennial; rhizomes and stolons present, the rhizomes usually shorter, but 

 similar to the stolons in other characters, stolons to 6 cm long, 1-2 mm wide; 

 blades of the basal leaves, 3-10 mm wide, to 30 cm long ; margins sparsely pubes- 

 cent, apex callose-tipped ; culms erect, slender, smooth, 20-40 cm tall, bearing 

 2-A leaves ; sheaths closed, pubescent at the throat with long white hairs ; blades 

 linear 2-4 (rarely 5) mm wide, to 6 cm long, margins sparsely pubescent to 

 glabrous ; inflorescence terminal, simple to compound, never decompound ; pedi- 

 cels 8-18 v loosely ascending, spreading or nodding, 1-4 cm long ; basal bract 

 erect, shorter than the inflorescence, leaf -like, green, the margins sparsely pubes- 

 cent, callose-tipped; other bracts of the inflorescence smaller, light brown to 

 hyaline fleeted with brown ; inner bract at the base of each pedicel usually trun- 

 cate with a. hyaline tip, glabrous to rarely pubescent ; the outer bract half as 

 long to as long as the inner, acuminate, margins pubescent; bracteols ovate- 

 lanceolate, truncate to acute, brown with hyaline margins to completely hyaline, 

 shorter than the flower; perianth segments similar, broadly lanceolate, pale 

 brown to stramineous with hyaline margins, entire, 3-4.5 mm long; stamens 6 

 shorter than the perianth, filaments linear, white, anthers linear usually twice 

 as long as the filaments; pistil erect, ovary trigonous pointed, style 1—1.5 mm 

 long filiform, stigmas 3, spreading 1.5 mm long; fruits equalling to slightly 

 longer than the perianth, acute, persistent base of the style present, light brown 

 to stramineous; seeds subglobose, purple to brown, 1-1.5 mm long; caruncle 

 large, slightly curved, 1-1.5 mm long. 



