134 GRAMINEAE (GRASS FAMILY) 



nearly flat or involute ; panicle purplish, 1-2 cm. long, pyramidal, the slendet 

 branches ascending ; pedicels hairy at the summit ; spikelets 5 mm. long ; glumes 

 shorter than the floret, mucronate ; callus-hairs less than half 

 the length of the scabrous lemma and palea, which are bristly- 

 bearded along the keels. (Calamagrostis Beck.) Sandy 

 swamps, pine-barrens of N. J. and N. C., rare. 



2. C. Iongif61ia (Hook.) Hack. Culms solitary, 6-18 dm. 

 high, from running rootstocks, stout ; sheaths usually pubescent, 

 at least on the margins ; leaves elongated, involute above and 

 tapering into a long thread-like point; panicle pale, 1.5-4.5 

 d m - long, narrow, the slender smooth branches erect or ascend- 

 ' , ; *!, T* ing ; spikelets 6-7 mm. long; glumes acute, the second equal to 

 h H i " or exceeding the floret; callus-hairs more than half the length 



of the smooth lemma and palea. (Calamagrostis Hook.) 

 Sandy shores, Ont. to Rocky Mts., south w. to 111. and Kan., and south westw. 

 July-Sept. FIG. 107. 



35. CALAMAGR6STIS Adans. REED BENT GRASS 



Spikelets 1-flowered ; rhachilla prolonged behind the palea into a hairy bristle 

 or pedicel ; glumes subequal, usually longer than the floret ; lemma awned on 

 the back, usually from below the middle, surrounded at base with copious long 

 hairs; palea shorter than the lemma, faintly 2-nerved. Tall often reed-like 

 perennials, with running rootstocks, simple mostly erect culms and many- 

 flowered panicles. (Name compounded of /cdXa/xos, a reed, and &ypw<ms, a 

 grass.) A difficult genus in which the awns and callus-hairs, although furnish- 

 ing the most used diagnostic features, are exceedingly variable. 



Awn bent, exserted more or less. 



Sheaths not bearded at the summit 1. C. Pickeringii. 



Sheaths bearded at the summit. 

 Palea about as long as the lemma; callus -hairs one fourth to one third 



as long 2. C. Porteri. 



Palea and callus-hairs three fourths as long as the lemma . . . 8. C. perplexa. 

 Awn straight, included. 

 Panicle loose and open, even after flowering. 



Spikelets 3-3.5 mm. long 4. C. canadensis. 



Spikelets 5-6 mm. long 5. C. Langsdorfar. 



Panicle contracted, strict, the short branches erect or appressed after 



flowering. 



Rudiment hairy throughout. 

 Panicle dense, more or less spike-like ; leaves involute. 



Leaves smooth, soft ; rootstock slender 6. C. neglecta, 



Leaves roughish, rigid ; rootstocks stouter 7. C. hyperborea. 



Panicle looser, the branches spreading at flowering time . . . 8. C. inexpansa. 

 Rudiment with copious long hairs at the tip 9. (7. cinnoides. 



* Awn strongly bent, exserted more or less ; callus-hairs usually much shorter 



than the lemma. 



1. C. Pickeringii Gray. Culms solitary or few, 3-5 dm. high, somewhat 

 rigid, scabrous below the panicle ; sheaths smooth ; blades flat, 4-10 cm. long, 

 4-5 mm. wide, erect ; panicle purplish, 7-12 cm. long, the branches erect or 

 ascending ; spikelets 4 mm. long ; glumes acute, exceeding the obtuse scabrous 

 lemma, which bears a short stout bent (not twisted) awn from below the 

 middle ; callus-hairs ^-\ the length of the lemma, wanting at the back. (C. 

 breviseta Scribn.) Mts. of N. Y. and N. E. to Nfd., and northw. ; locally at 

 Andover, Mass. (J. BoUnsori). Aug.-Sept. 



Var. lacustris (Kearney) Hitchc. Culms taller (5-10 dm. high); rootstocks 

 stouter ; leaves more or less involute ; panicle usually longer ; callus-hairs f-f as 

 long as the lemma. Mts. of N. E., and along the Great Lakes to Minn. 



2. C. PortSri Gray. Culms slender, 6-12 dm. high; blades 1.5-3 dm. long, 

 4-8 mm. wide, flat, taper-pointed, very rough, bearded on the sides at the base ; 

 ligule 4-5 mm. long ; panicle narrow, 8-16 cm. long, rather loosely flowered, the 



