1901] Fernald, — Scirpus supinus and its Allies. 251 
SYNOPSIS OF SPECIES. 
* Achenes transversely wrinkled; bristles normally absent. 
+ Achenes distinctly triangular in cross-section. 
S. suPINUS, L. Plant 2.5 dm. or less high; the involucral leaf 
erect and very elongated, nearly or quite equalling the true culm: 
spikelets ovoid-lanceolate, acutish, 5 to 12 mm. long: the ovate or 
suborbicular ferruginous round-tipped scales short-mucronate: styles 
3-cleft. — Spec. 49; Reichenb. Ic. Fl. Germ. viii. t. 302; Boeckeler, 
Linnaea, xxxvi. 699, in part; etc. — Continental Europe. 
S.saximontanus. Very slender, 2 cm. to 3 dm. high, sparingly 
short-leafy at base; the erect involucral leaf one-half to one-fourth 
as long as the true culm: spikelets 1 to 4, oblong-cylindric, acute, 5 
to 12 mm. long: scales ovate, cuspidate-acuminate, the margins 
pale brown: styles 3-cleft: achenes dark brown or black, 1.5 mm. 
long, one face slightly broader than the other two. — S. supinus, 
Gray, Man. Ed. 5, 563; Watson, Proc. Am. Acad. xviii. 171; Hemsl. 
Biol. Cent.-Am. Bot. iil. 462; not L. S. Hallit, Britton, Trans. N. 
Y. Acad. Sci. xi. 77, in part, not Gray. — CoLorapo, banks of La 
Poudre River, Greely, Sept. 20, 1872 (Æ. Z. Greene): Texas, with- 
out locality (Charles Wright): Ciboto, June, 1847 (F. Lindheimer) : 
San Luis Porosi, low ground, Penasco, 1876 (7. G. Schaffner, no. 
571). 
-— + Achenes plano-convex. 
S. HALLIL, Gray. Slender, r to 4 dm. high; the erect involucral 
leaf usually one-half to one-fourth as long as the true culm: umbel 
rarely branched, of 1 to 7 linear- or oblong-clyindric acute spike- 
lets o.5 to 1.5 cm. long: scales ovate, cuspidate-acuminate, the 
margins brownish: styles 2-cleft. — Man. ed. 3, addend. xcvii; 
Britton, l. c., in part, and in Britton and Brown, Ill. Fl. i. 264, fig. 
615. S. supinus, var. Halli’, Gray, Man. ed. 5, 563. — MASSA- 
CHUsETTs, Winter Pond, Winchester, Aug., Sept. (Hitchings, Boott, 
Faxon, et a): ILLINOIS, Menard Co., 1861 (E. May): FLORIDA, 
Indian River (Curtiss, no. 3118*): MISSOURI, St. Louis, Sept., 1845 
(Geo. Englemann). 
* * Achenes smooth or merely pitted. 
+ Achenes unequally bi-convex or lenticular. 
S. DEBILIS, Pursh. Comparatively stout, 6 dm. or less high; the 
erect or deflexed involucral leaf usually one-fourth to one-eighth as 
long as the true culm: spikelets 1 to 12, ovoid-oblong, bluntish, 0.5 
to 1 cm. long: scales orbicular to broad-ovate, with tawny margins: 
achenes more or less pitted, broadly obovoid, contracted to a short 
