90 PROCEEDINGS OF THE ACADEMY OF 



glumis inaequalibus, inferiore linear! acuta valvula breviore, superiore ovata 

 acuta valvula parum breviore ; valvulis inaequalibus aut sequalibus muticis. 



Dry plains at the base of the Rocky Mountains. Nuttall. 



Smooth and of a pale green ; leaves and sheaths of abortive culms, nume- 

 rous at the base ; panicle somewhat spreading, with the lower branches (23 

 inches long) appressed upward, with many flowers on short branchlets ; 

 glumes and valves very variable, and more or less unequal, green, with 

 chartaceous margins ; stem leaves 4 6 inches long and the upper portions 

 lilamentose. 



Sporobulus (Vilfa) d i f f u s i s s i m u s, s. n. Tota glabra ; culmo erecto 

 simplici 2 pedali ; vaginis internodio brevioribus ; ligulis pauci-pilosis ; foliis 

 8 12-policaribus planis aut convolutis apice filiformibus ; panicula diffusa 

 ampla pyriinidale ; radiis filiformibus patentibus ramosis ; glumis hyalinis 

 ovatis muticis inaequalibus valvula brevioribus ; valvulis muticis lato- ovatis 

 subaequalibus albo-hyalinis caryopsi parum longioribus ; caryopsi ellipsoidea 

 obtusa. 



Western Texas. 



Panicle spreading, its lower branches 46 inches long and refracted ; upper 

 sheath 3 4 inches below the panicle ; flowers rather numerous, on short 

 branchlets. 



Vilfa (Sporobulus) Sabeana, s. n. Decumbens culmis basi numerosis 

 teretibus ; foliis planis (2 6-policar. ) marginibus scabris ; vaginis internodio 

 brevioribus faucibus villosis ; paniculis terminalibus lateralibusque patentibus 

 subpyrimidalibus et albescentibus ; radiis capillaribus infimis verticellatis, su- 

 perioribus alternatis 10 15-floris ; glumis inaequalibus, inferiore parva su- 

 periore f breviori ; valvulis a?qualibus acutis ; glumis et paleis albo-hyalinis ; 

 caryopsi ovoidea obtusa castanea. 



San Saba County, Texas. 



Culms 1 2 feet long, often divaricately branched near the root ; panicles 

 3 4 inches in length ; lower 12 15 lines long ; seeds caducous ; when ma- 

 ture the glumes and valves are translucent ; upper glume as long as the 

 valves. 



Agrcstis aquatic a, s. nov. Radice fibrosa repente ; culmis decumbent i- 

 bus teretibus striatulis glabris; foliis linearibus planis 2 3-policaribus; ligulis 

 scabrosis ovatis 5 9-nervosis acutis vel subobtusis ; vaginis striatulis inter- 

 nodio brevioribus ; panicula coarctata decomposita densinora ; radiis filiformi- 

 bus, subverticellatis ; glumis sequalibus scabrosis acutis vel subobtusis ovatis ; 

 valvulis ovatis subacutis aut obtusis gluma A brevioribus callo utrinque breve 

 piloso ; rudimento nullo. 



On small floating islands in the mill-pond or large spring at San Saba, the 

 capital of San Saba County. 



Achenia ovate, smooth; stems 1J 2 feet long, decumbent, growing in 

 dense tufts ; leaves 2 3 inches long and 2 3 lines wide ; valves transparent. 



Agrostis scabriuscula, s. n. Radice repente fibrosa; culmo basi pro- 

 cumbente erecto glabro tereti 12 15-policari ; vaginis scabriusculis internodio 

 brevioribus ; ligula ovata acuta integerrima seu parum fissa ; foliis scabris 

 planis 3 4-policaribus, 2 3 lin. latis ; panicula ampla interrupte rubescente 

 7 8-policari ; radiis scabris semiverticellatis inaequalibus 5 7-nis apice ra- 

 mosis et subdensifloris, inferne 4 5-policaribus ; glumis parum inaequalibus 

 acutis scabris valvula solitaria longioribus ; callo antrorsuni brevissime bar- 

 bato ; rudimento nullo. 



Oregon ; Columbia Plains. Nuttall. 



Branches of the panicle semi-verticellate and naked below, about midway 

 verticellately branched, the flowers being near the summit of the branchlets, 

 on pedicels more or less elongated; pedicels one- flowered ; base of the panicle 

 often sheathed. 



[Feb. 



