GENUS 68. 



GRASS FAMILY. 



231 



i. Acamptoclados sessilispicus (Buckley) Nash. 

 Stiff Prairie-grass. Fig. 556. 



Eragrostis sessilispica Buckley, Proc. Acad. Phila. 1862 : 97. 



1862. 



Diplachne rigida Vasey, Grasses S. W., Part 2. pi. 41. 1891. 

 A. sessilispicus Nash, in Small, Fl. SE. U. S. 140. 1903. 



Culms 8'-3i tall, erect, simple, smooth and glabrous. 

 Sheaths short, crowded at the base of the culm, smooth, 

 pilose at the summit ; ligule a ring of short hairs ; blades 

 2-6' long, i"-ii" wide, rough above, glabrous or spar- 

 ingly pilose beneath ; panicle 8'-i6' in length, the 

 branches stout, rigid, widely diverging ; spikelets scat- 

 tered, closely sessile, appressed, 5-i2-flowered, 4"-7" 

 long, empty scales about equal in length, acute; flower- 

 ing scales very acute, about 2" long, the lateral nerves 

 very prominent. 



Prairies, Kansas to Texas. Aug.-Sept. 



69. BULBILIS Raf. Am. Month. Mag. 4: 190. 1819. 

 [BuCHLoii Engelm. Trans. St. Louis Acad. i : 432. pi. 14. figs. 1-17. 1859.] 



A perennial stoloniferous monoecious or apparently dioecious grass with flat leaf-blades 

 and spicate inflorescence. Staminate spikelets borne in two rows on one side of the rachis, 

 the spikes at the summit of the long and exserted culms. Pistillate spikelets in spike-like 

 clusters of 2 or 3, on very short culms, scarcely exserted from the sheath. Stamens 3. 

 Styles distinct, long. Stigmas elongated, short-plumose. Grain ovate, free, enclosed in the 

 scale. [Name apparently from the supposed bulb-like base of old plants.] 



A monotypic genus of central North America. 



i. Bulbilis dactyloides (Xutt.) Raf. Buf- 

 falo-grass. Early Mesquite. Fig. 557. 



Sesleria dactyloides Nutt. Gen. i : 65. 1818. 

 Buchloe dactyloides Engelm. Trans. St. Louis Acad. 



i : 432. 1859. 

 Bulbilis dactyloides Raf. ; Kuntze, Rev. Gen. PI. 763. 



1891. 



Culms bearing staminate flowers 4'-i2' tall, 

 erect, slender, naked above, smooth and glabrous ; 

 those bearing pistillate flowers $'-3' long, much 

 exceeded by the leaves ; ligule a ring of short 

 hairs; blades i" wide or less, more or less papil- 

 lose-hirsute, those of the staminate culms i'-4' 

 long, erect, those of the stolons and pistillate 

 culms i' long or less, spreading; staminate spikes 

 2 or 3, approximate ; spikelets 2"-2i" long, flat- 

 tened, 2-3-flowered, the empty scales i-nerved, 

 the flowering 3-nerved ; pistillate spikelets ovoid, 

 the outer scales indurated. 



On plains and prairies, Minnesota to Saskatchewan, 

 south to Arkansas, Texas and northeastern Mexico. 

 A valuable fodder grass. June-July. 



70. MUNROA Torr. Pac. R. R. Rept. 4: 158. 1856. 



Low diffusely branched grasses, with flat pungently pointed leaf-blades crowded at the 

 nodes and the ends of the branches. Spikelets in clusters of 3-6, nearly sessile in the axils 

 of the floral leaves, 2-5-flowered, the flowers perfect. Two lower scales empty, lanceolate, 

 acute, i-nerved, hyaline ; flowering scales larger, 3-nerved ; I or 2 empty scales sometimes 

 present above the flowering ones; palet hyaline. Stamens 3. Styles distinct, elongated. 

 Stigmas barbellate or short-plumose. Grain free, enclosed in the scale and palet. [In honor 

 of Gen. William Munro, English agrostologist.] 



Three known species, the following typical one of the plains of North America, the others 

 South American. 



