200 



CYPERACEAE (SEDGE FAMILY) 



5. R. Torreyana Gray. Culm nearly terete, slender; leaves 

 involute-filiform ; cymes panicled, somewhat loose, the ascend- 

 ing brown spikelets mostly pediceled; achene 

 compressed, oblong-obovoid, longer than the 



bristles, thrice the length of the broad com- 

 pressed-conical tubercle. Swamps and bogs, 

 East Washington, N. H. (C. F. Parker} ; 

 pine-barrens of N. J. to Ga. July-Oct. FIG. 

 317. 



6. R. inexpansa (Michx.) Vahl. Culm 

 triangular, slender ; leaves narrowly linear, 

 2-3 mm. wide, becoming involute ; spikelets 

 spindle-shaped, mostly pediceled, in drooping 

 panicles; achene oblong, half the length of 

 the slender bristles, twice the length of the 



rreyana. tr i an g u i ar _ su b u i ate tubercle. Low grounds, 

 Va. to Ga. July-Sept. FIG. 318. 



* * Achene smooth and even. 



318. R. inexpansa. 



310. 11. fusca. 



t- Bristles 6, long and conspicuous, upwardly denticulate. 



7. R. fusca (L.) Ait. f. Loosely stoloniferous ; culm 2-6" 

 dm. high ; leaves bristle-form, channeled; spikelets ovoid- 

 fusiform, few, clustered in 1-4 loose heads (chestnut-color) 

 overtopped by the slender bracts ; achene obo- 

 void, about | the length of the bristles, nearly 

 equaling the triangular-sword-shaped acute 

 tubercle, which is rough-serrulate on the mar- 

 gins. Boggy places, Nfd. to Out., s. to Del. 

 and Mich. July-Sept. (Eu.) FIG. 319. 



8. R. graci!6nta Gray. Culms very slender, 3-8 dm. high ; g2 

 leaves narrowly linear; spikelets ovoid, in 2-4 small clusters, 



the lateral long-peduncled ; achene ovoid, rather shorter than 

 the bristles, about the length of the flat-awl-shaped tubercle. 

 Low grounds, s. N. Y. and N. J. to Fla. Aug., Sept. (W. I., 

 S. A.) FIG. 320. 



9. R. oligantha Gray. Culm and leaves filiform, 1.5-4 

 dm. high ; spikelets very few (1-4), ovoid-fusiform ; bristles 

 plumose below the middle; achene obovoid-oblong. bearing a 

 ^nical tubercle -J its length. Del. to Fla. July, Aug. 



321. R. oligantha. FiG. 321. 



f- t- Bristles none, or 1-3 and minute ; spikelets pale, l-flowered. 



10. R. pallida M. A. Curtis. Culm (3-8 dm. high) acutely 

 triangular ; leaves and spikelets as in the next species, but only 

 a terminal dense cluster, which is less white or turns pale 

 reddish-tawny ; achene obovoid-lenticular, tipped with a minute 

 //r/./v.s-.w and apiculate tubercle; the delicate bristles 4-5 times 

 shorter or obsolete. Bogs in pine-barrens, N. J. and N. C. 

 Aug., Sept. (VV. I., S. A.) FIG. 322. 



322. R. pallida. 



--*- Bristles loixt. <lrnti<'nlnte tl<>n-)ttf(/r<1, or both ways in no. 1 ">. 



+ Spikclt'fx if hid' <>r ii'hifish, becoming tawny with Offe, perfecting n//!// n 

 flower ; stamens usually 2 ; bristles 9-12, or even 20*. 



11. R. alba (L.) Vahl. Culm slender (1.5-6 dm. high), triangular above; 

 leaves narrowly linear or almost bristle-form; spikelets lanceolate, densely 

 crowded in a head-like terminal corymb (O.f>-1. f> cm. broad) and usually one o'r 

 two lateral ones ; achene oblong-obovate with a narrowed base, scarcely longer 

 than the flattened-awl-shaped tubercle, shorter than the bristles. Bogs. Nt'd 



