Spikt'K'N <»ii j)('«li('i'l8 5-15 iiini. loiij,'; oiiipty pliiincrt Kt'rrnliitc oti 

 the Hiii^ili" luTVf. .sccoiitl tlio longer, about 1 iiini. loiiif. iK'sidcs a 

 short brislNs llonil ;;liiiiie lunci'olutc, ;{-nervi'(l, 'Z-',] iiiiii. loiii,'. tlif 

 awii (i-10 iim). loii;^'; imlt-ii ueiite. us wkk- uiul lus long as its gluniL'. 

 Antlicrs ;J ill ntiniliiT. 1.4 mm. long. 



Mexico (I?i() HlaiKo). I'ltlnwr 523, b'lWrx. 



WH. M. laxiflora Srrihn. inol. 



A rather slender erect light green tufted [)erennial, about 90 

 em. high. Sheaths shorter than the internodes; ligule tliin, la.sce- 

 rate, acute. 5 (i mm. long; blades scabrous, involute or condu|)li- 

 cate, those of the culm \\-\, and 4-1.') cm. long, O.A-O.T rum. 

 diam. Panicles terminal, thin, purplish, lanceolate (or spreading?), 

 about 15 cm. long, rays mostly in twos and threes, erect, sparingly 

 branched, bearing 8-15 spikelets on the ternunal lialf. Spikclets 

 on pedicels 1-4 mm. long, empty glumes ovate, acute, obscurely 

 1-nerved, set^oml the longer. 1.5 mm. long. 3-nerved; iloral glinne 

 seabrid. o-ncrvt'd. ;?.T-4 mm. long, linear wlu'ii spread, acute or 

 bearing a short briatlc; i)aloa obtuse when spread, as long as its 

 glume. 



Mexico, J'riiH/h- 141 "3. 



Cool sloj)es of {\h' Su'rra Madre, Mexico. 



30. M. articulata Scribn. Proc. Acad. Phila. 208 (1801). 



An erect densely tufted perennial, GO-SO cm. high. Tjcaves of 

 sterile shoots nearly as high as the culms; shciillis com[)ressed. 12- 

 18 cm. long; ligule very stout, rigid. 5-7 mm. long; blades strongly 

 involute or condu])licate. smooth, 0.7-1 mm. diam.. long-pointed, 

 articulate at the sheaths, leaving the stout ligule proje(!ting. Pan- 

 icle loosely spikelike, about .'50 cm. long, longest rays ;>-G cm. long. 

 Spikelets linear-lanceolate, 4 mm. long; empty glumes hmceo- 

 late, 1-nerved, first 2.5 mm. long, second 3.2 mm. long; Iloral 

 glume with a tuft of short hairs at the base, 3-uerved, bearing a 

 slender tortuose awn 2-2.5 cm. long. 



Mexico (San Luis Potosi). Prinijh 3013. 



On dry calcareous hills. 



40. M. Berlandieri Triu. Mem. Acad. St. Petcrsb. (VI.) 0.2 : 209 

 (1845). 



